2024/08/05 更新

写真a

フクマ ヤスヒロ
福間 康裕
FUKUMA Yasuhiro
Scopus 論文情報  
総論文数: 0  総Citation: 0  h-index: 15

Citation Countは当該年に発表した論文の被引用数

所属
大学院情報工学研究院 物理情報工学研究系
職名
教授
メールアドレス
メールアドレス
ホームページ
外部リンク

研究キーワード

  • スピントロニクス

研究分野

  • ナノテク・材料 / ナノマイクロシステム

  • ものづくり技術(機械・電気電子・化学工学) / 電気電子材料工学

取得学位

  • 山口大学  -  博士(工学)   2002年03月

学内職務経歴

  • 2019年04月 - 現在   九州工業大学   大学院情報工学研究院   物理情報工学研究系     教授

  • 2016年05月 - 2019年03月   九州工業大学   大学院情報工学研究院   電子情報工学研究系     准教授

論文

  • Charge-spin interconversion in nitrogen sputtered Pt via extrinsic spin Hall effect 査読有り 国際誌

    Shashank U., Kusaba Y., Nakamura J., Mathew A.J., Imai K., Senba S., Asada H., Fukuma Y.

    Journal of Physics Condensed Matter   36 ( 32 )   2024年08月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    We experimentally investigate the charge-spin interconversion by introducing a lighter impurity, namely nitrogen (N) into Pt by varying the nitrogen gas flow rate, Q from 0 to 20%, and studying the Onsager reciprocity of spin Hall effect (SHE) via complementary methods of spin-torque ferromagnetic resonance and spin-pumping inverse SHE measurements, respectively. We notice a reduction in the crystalline nature of Pt upon nitrogen incorporation. We observe the influence of extrinsic side-jump scattering induced SHE by measuring the spin Hall efficiency, θ SH in a wide temperature range from 10 to 296 K. This work establishes the incorporation of N in Pt by using sputtering, to enhance the SHE via extrinsic scattering as well as to observe the reciprocal effects of charge-spin interconversion.

    DOI: 10.1088/1361-648X/ad42ee

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  • Realization of logic operations via spin-orbit torque driven perpendicular magnetization switching in a heavy metal/ferrimagnet bilayer 査読有り 国際誌

    Jacob Mathew A., Gao Y., Wang J., Mohammadi M., Awano H., Takezawa M., Asada H., Fukuma Y.

    Journal of Applied Physics   135 ( 21 )   2024年06月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Programmable and non-volatile spin-based logic devices have attracted significant interest for use in logic circuits. Realization of logic operations via spin-orbit torque (SOT) driven magnetization switching could be a crucial step in the direction of building logic-in-memory architectures. In this work, we demonstrate experimentally, the realization of four logic operations in a heavy metal/ferrimagnet bilayer structure via SOT switching. We also propose a general scheme for choosing input parameters to achieve programmable logic operations. The bulk and tunable perpendicular magnetic anisotropy and relatively lower saturation magnetization in ferrimagnets are found to make them more energy efficient in performing logic operations, as compared to conventional ferromagnets. Thus, ferrimagnets are promising candidates for use in logic-in-memory architectures, leading to the realization of user-friendly spin logic devices in the future.

    DOI: 10.1063/5.0209089

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  • Classification tasks using input driven nonlinear magnetization dynamics in spin Hall oscillator 査読有り 国際誌

    Mohan J.R., Mathew A.J., Nishimura K., Feng R., Medwal R. (Indian Institute of Technology Kanpur), Gupta S., Rawat R.S. (Nanyang Technological University), Fukuma Y.

    Scientific Reports   13 ( 1 )   2023年12月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    The inherent nonlinear magnetization dynamics in spintronic devices make them suitable candidates for neuromorphic hardware. Among spintronic devices, spin torque oscillators such as spin transfer torque oscillators and spin Hall oscillators have shown the capability to perform recognition tasks. In this paper, with the help of micromagnetic simulations, we model and demonstrate that the magnetization dynamics of a single spin Hall oscillator can be nonlinearly transformed by harnessing input pulse streams and can be utilized for classification tasks. The spin Hall oscillator utilizes the microwave spectral characteristics of its magnetization dynamics for processing a binary data input. The spectral change due to the nonlinear magnetization dynamics assists in real-time feature extraction and classification of 4-binary digit input patterns. The performance was tested for the classification of the standard MNIST handwritten digit data set and achieved an accuracy of 83.1% in a simple linear regression model. Our results suggest that modulating time-driven input data can generate diverse magnetization dynamics in the spin Hall oscillator that can be suitable for temporal or sequential information processing.

    DOI: 10.1038/s41598-023-34849-7

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  • Room-Temperature Charge-to-Spin Conversion from Quasi-2D Electron Gas at SrTiO<inf>3</inf>-Based Interfaces 査読有り 国際誌

    Shashank U., Deka A., Ye C., Gupta S., Medwal R. (Indian Institute of Technology Kanpur), Rawat R.S. (Nanyang Technological University), Asada H., Renshaw Wang X., Fukuma Y.

    Physica Status Solidi - Rapid Research Letters   17 ( 6 )   2023年07月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Interfacial two-dimensional electron gases (2DEG), especially the SrTiO3-based ones at the unexpected interface of insulators, have emerged to be promising candidates for efficient charge–spin interconversion. Herein, to gain insight into the mechanism of the charge–spin interconversion, quasi-2DEG between insulating SrTiO3 and two types of aluminum-based amorphous insulators, namely SrTiO3/AlN and SrTiO3/Al2O3, are focused on and their charge-to-spin conversion efficiency is estimated. The two types of amorphous insulators are selected to probe the overlooked contribution of oxygen vacancy. A mechanism to explain the results of spin–torque ferromagnetic resonance measurements is proposed and an analysis protocol to reliably estimate in quasi-2DEG is developed. The resultant, thickness of the 2DEG, is estimated to be 0.244 and 0.101 nm−1 for SrTiO3/AlN and SrTiO3/Al2O3, respectively, which are strikingly comparable to their crystalline counterparts. Furthermore, a large direct current modulation of resonance linewidth in SrTiO3/AlN samples is developed, confirming and attesting an oxygen vacancy-enabled charge–spin conversion. The findings emphasize the defects' contribution-, especially in oxide-based low-dimensional systems, and provide a way to create and enhance charge–spin interconversion via defect engineering.

    DOI: 10.1002/pssr.202200377

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  • Interfacial Origin of Unconventional Spin-Orbit Torque in Py/γ−$\gamma -$IrMn<inf>3</inf> 査読有り 国際誌

    Kumar A., Gupta P., Chowdhury N., Khan K.I.A., Shashank U., Gupta S., Fukuma Y., Chaudhary S., Muduli P.K. (Indian Institute of Technology Delhi)

    Advanced Quantum Technologies   6 ( 7 )   2023年07月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Angle-resolved spin-torque ferromagnetic resonance measurements are carried out in heterostructures consisting of Py (Ni81Fe19) and a noncollinear antiferromagnetic quantum material (Formula presented.) IrMn3. The structural characterization reveals that (Formula presented.) IrMn3 is polycrystalline in nature. A large exchange bias of 158 Oe is found in Py/ (Formula presented.) IrMn3 at room temperature, while (Formula presented.) IrMn3/Py and Py/Cu/ (Formula presented.) IrMn3 exhibit no exchange bias. Regardless of the exchange bias and stacking sequence, a substantial unconventional out-of-plane anti-damping torque is observed when (Formula presented.) IrMn3 is in direct contact with Py. The magnitude of the out-of-plane spin-orbit torque efficiency is found to be twice as large as the in-plane spin-orbit torque efficiency. The unconventional spin-orbit torque vanishes when a Cu spacer is introduced between Py and (Formula presented.) IrMn3, indicating that the unconventional spin-orbit torque in this system originates at the interface. These findings are important for realizing efficient antiferromagnet-based spintronic devices via interfacial engineering.

    DOI: 10.1002/qute.202300092

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  • Ferromagnetic resonance excited by interfacial microwave electric field: the role of current-induced torques 査読有り 国際誌

    Deka A., Rana B., Otani Y.C., Fukuma Y.

    Journal of Physics Condensed Matter   35 ( 21 )   2023年06月

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    担当区分:最終著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Excitation of magnetization dynamics in magnetic materials, especially in ultrathin ferromagnetic films, is of utmost importance for developing various ultrafast spintronics devices. Recently, the excitation of magnetization dynamics, i.e. ferromagnetic resonance (FMR) via electric field-induced modulation of interfacial magnetic anisotropies, has received particular attention due to several advantages, including lower power consumption. However, several additional torques generated by unavoidable microwave current induced because of the capacitive nature of the junctions may also contribute to the excitation of FMR apart from electric field-induced torques. Here, we study the FMR signals excited by applying microwave signal across the metal-oxide junction in CoFeB/MgO heterostructures with Pt and Ta buffer layers. Analysis of the resonance line shape and angular dependent behavior of resonance amplitude revealed that apart from voltage-controlled in-plane magnetic anisotropy (VC-IMA) torque a significant contribution can also arises from spin-torques and Oersted field torques originating from the flow of microwave current through metal-oxide junction. Surprisingly, the overall contribution from spin-torques and Oersted field torques are comparable to the VC-IMA torque contribution, even for a device with negligible defects. This study will be beneficial for designing future electric field-controlled spintronics devices.

    DOI: 10.1088/1361-648X/acc377

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  • Evaluation of Memory Capacity and Time Series Prediction Using a Spin Hall Oscillator as Reservoir 査読有り 国際誌

    Mathew A.J., Mohan J.R., Feng R., Medwal R. (Indian Institute of Technology Kanpur), Gupta S., Rawat R.S. (Nanyang Technological University), Fukuma Y.

    IEEE Transactions on Magnetics   59 ( 6 )   2023年06月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Spintronic devices, such as spin Hall oscillators (SHOs) and spin transfer torque oscillators, have become popular candidates for use as the reservoir in the reservoir computing (RC) architecture. The memory capacity of a reservoir quantifies the amount of information retained at any given time, indicating its significance for different RC tasks. In this work, we consider an SHO, consisting of a bilayer structure of platinum/Permalloy, as the reservoir. Using micromagnetic simulations, we evaluate the change in memory capacity of the SHO system as the magnetization dynamics varies from transient state oscillations to limit cycle oscillations. We also perform a three-bit parity task to study the performance of the oscillator in carrying out a nonlinear task. A time series prediction task, namely, the nonlinear auto regressive moving average (NARMA)2 task, is also performed. The results of both tasks confirm a correlation between the evaluated memory capacity of the reservoir and its efficiency in performing temporal tasks. The best performance in RC tasks is observed when the output magnetization dynamics of the oscillator consists of both transient state and limit cycle oscillations.

    DOI: 10.1109/TMAG.2023.3266517

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  • Anisotropy-assisted bias-free spin Hall nano-oscillator 査読有り 国際誌

    Manna S., Medwal R. (Indian Institute of Technology Kanpur), Gupta S., Mohan J.R., Fukuma Y., Rawat R.S. (Nanyang Technological University)

    Applied Physics Letters   122 ( 7 )   2023年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Ferromagnet/nonmagnet (FM/NM) bilayer-based spin Hall nano-oscillators (SHNOs) - a sub-class of spintronic oscillator devices - have promising potential toward realizing low-power physical reservoir computing systems because of their inherent nonlinearity and miniature form factor. However, most of the studies on SHNOs indicate that an external biasing magnetic field is necessary for their operation, creating a bottleneck for their practical implementation in designing small and compact RC hardware. In this report, using micromagnetic simulation, we demonstrate biasing field-free operation of a FM/NM bilayer-based SHNO by exploiting the magnetic anisotropy. Our results reveal that the magnetic anisotropy in the FM layer provides active control over the DC tunability of auto-oscillation frequency and the threshold value of current needed for sustained auto-oscillations. We show that the increase in uniaxial anisotropy substantially modifies the spatial profile of auto-oscillation and eventually leads to the reduction in the threshold current for auto-oscillation, which could be utilized to design low-power computing hardware using SHNO devices.

    DOI: 10.1063/5.0130624

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  • Disentanglement of intrinsic and extrinsic side-jump scattering induced spin Hall effect in N-implanted Pt 査読有り 国際誌

    Shashank U., Nakamura Y., Kusaba Y., Tomoda T., Nongjai R., Kandasami A., Medwal R., Rawat R.S., Asada H., Gupta S., Fukuma Y.

    Physical Review B   107 ( 6 )   2023年02月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    The rapidly evolving utilization of spin Hall effect (SHE) arising from spin-orbit coupling in 5d transition metals and alloys has made giant strides in the development of designing low-power, robust, and nonvolatile magnetic memory. Recent studies, on incorporating nonmetallic lighter elements such as oxygen, nitrogen, and sulfur into 5d transition metals, have shown an enhancement in dampinglike torque efficiency θDL due to the modified SHE, but the mechanism behind this enhancement is not clear. In this paper, we study θDL at different temperatures (100-293 K) to disentangle the intrinsic and extrinsic side-jump scattering induced SHE in N-implanted Pt. We observe a crossover of intrinsic to extrinsic side-jump mechanism as the implantation dose increases from 2×1016 to 1×1017ions/cm2. A sudden decrease in the intrinsic spin Hall conductivity is counterbalanced by the increase in the extrinsic side-jump induced SHE efficiency. These results conclude that studying θDL as a function of implantation dose, and as a function of temperature, is important to understand the physical mechanism contributing to SHE.

    DOI: 10.1103/PhysRevB.107.064402

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  • Secondary Spin Current Driven Efficient THz Spintronic Emitters 査読有り 国際誌

    Agarwal P., Yang Y., Medwal R. (Indian Institute of Technology Kanpur), Asada H., Fukuma Y., Battiato M., Singh R. (Nanyang Technological University)

    Advanced Optical Materials   11 ( 23 )   2023年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Femtosecond laser-induced photoexcitation of ferromagnet (FM)/heavy metal (HM) heterostructures has attracted attention by emitting broadband terahertz frequencies. The phenomenon relies on the formation of an ultrafast spin current, which is primarily attributed to the direct photoexcitation of the FM layer. However, during the process, the FM layer also experiences a secondary excitation led by the hot electrons from the HM layer that travel across the FM/HM interface and transfer additional energy in the FM. Thus, the generated secondary spins enhance the total spin current formation and lead to amplified spintronic terahertz emission. These results emphasize the significance of the secondary spin current, which even exceeds the primary spin currents when FM/HM heterostructures with thicker HM are used. An analytical model is developed to provide deeper insights into the microscopic processes within the individual layers, underlining the generalized ultrafast superdiffusive spin-transport mechanism.

    DOI: 10.1002/adom.202301027

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  • Pulsed Hot Dense Oxygen Plasma Irradiation of Platinum for Improved Spin Hall Effect 査読有り 国際誌

    Kumar S., Manna S., Mohan J.R., Shashank U., Vas J.V., Mishra M., Gupta S., Asada H., Fukuma Y., Rawat R.S. (Nanyang Technological University), Medwal R. (Indian Institute of Technology Kanpur)

    SPIN   14 ( 2 )   2023年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The impurity incorporation in host high spin-orbit coupling materials like platinum (Pt) has shown improved charge-to-spin conversion e±ciency by modifying the up-spin and down-spin electrons trajectories via bending or skewing them in opposite directions. This enables e±cient generation, manipulation, and transport of spin currents. In this study, we irradiated the Pt thin films with pulsed hot dense oxygen plasma in non-focus mode operation and analyzed the spin Hall angle of the oxygen plasma irradiated Pt films using spin torque ferromagnetic resonance (ST-FMR). Our results demonstrate a 2.4 times enhancement in the spin Hall angle after transient oxygen plasma treatment of Pt as compared to pristine Pt. This improvement might be because of the introduction of disorder and defects in the Pt lattice due to transient oxygen plasma processing, which enhanced the spin-orbit coupling and leads to more e±cient charge-to-spin conversion without breaking the spin-orbit torque symmetries. Our findings offer a new method of dense plasma focus device-based modification of material for the development of advanced spintronic devices based on Pt and other heavy metals.

    DOI: 10.1142/S2010324723400246

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  • Modelling in-device inference and classification of binary digits using nonlinear dynamics of spin Hall oscillator 査読有り

    Mohan J.R., Yamanaka C., Feng R., Mathew A.J., Nakamura Y., Medwal R. (Indian Institute of Technology Kanpur), Gupta S., Rawat R.S. (Nanyang Technological University), Fukuma Y.

    2023 IEEE International Magnetic Conference - Short Papers, INTERMAG Short Papers 2023 - Proceedings   2023年01月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(国際会議プロシーディングス)

    In this work, we employ micromagnetic modelling of a spin Hall oscillator for a direct inference and classification of binary digit inputs. The spectral characteristics of the oscillation is utilized for the classification. We observed a direct inference of binary digit inputs up to a sequence of four binary digits. Subsequently, handwritten digit image recognition is tested with the Modified National Institute of Standards and Testing (MNIST) handwritten digit database and acquired an accuracy of 88.6% with a linear classifier network.

    DOI: 10.1109/INTERMAGShortPapers58606.2023.10228745

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  • Piezoelectric Strain Control of Terahertz Spin Current 査読有り 国際誌

    Chaurasiya A., Li Z., Medwal R., Gupta S., Mohan J.R., Fukuma Y., Asada H., Chia E.E.M., Rawat R.S.

    Advanced Optical Materials   10 ( 24 )   2022年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Electrical control of photogenerated terahertz (THz) spin current pulses from a spintronic emitter has been at the forefront for the development of scalable, cost-efficient, wideband optospintronic devices. Artificially combined ferroelectric and ferromagnet heterostructure provides the potential avenue to deterministically control the phase of THz spin current pulse through piezoelectric strain. Here, the electric field-mediated piezoelectric strain control of photogenerated THz spin current pulse from a multiferroic spintronic emitter is demonstrated. The phase reversal of the THz spin current pulse is obtained from the combined effect of piezoelectric strain and a small magnetic field applied opposite to the initial magnetization of the ferromagnet. The piezoelectric strain-controlled phase switching of THz spin current thus opens a door to develop efficient strain engineered scalable on-chip THz spintronics devices.

    DOI: 10.1002/adom.202201929

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  • Electric field induced parametric excitation of exchange magnons in a CoFeB/MgO junction 査読有り 国際誌

    Deka A., Rana B., Anami R., Miura K., Takahashi H., Otani Y., Fukuma Y.

    Physical Review Research   4 ( 2 )   2022年06月

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    担当区分:最終著者, 責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Inspired by the success of field-effect transistors in electronics, electric field controlled magnetization dynamics has emerged as an important integrant in low-power spintronic devices. Here, we demonstrate electric field induced parametric excitation for CoFeB/MgO junctions by using interfacial in-plane magnetic anisotropy (IMA). When the IMA and the external magnetic field are parallel to each other, magnons are efficiently excited by electric field induced parametric resonance. The corresponding wavelengths are estimated to be tuned down to exchange interaction length scales by changing the input power and frequency of the applied voltage. A generalized phenomenological model is developed to explain the underlying role of the electric field torque. Electric field control of IMA is shown to be the origin for excitation of both uniform and parametric resonance modes in the in-plane magnetized sample, a crucial element for purely electric field induced magnetization dynamics. Electric field excitation of exchange magnons, with no Joule heating, offers a good opportunity for developing nanoscale magnonic devices and exploring various nonlinear dynamics in nanomagnetic systems.

    DOI: 10.1103/PhysRevResearch.4.023139

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  • Investigation of structural, magnetic and electronic properties of FeTa films for varying Ta concentration at different annealing temperatures 査読有り

    Jafri Y., Singh S., Gupta S., Fukuma Y., Sharma K., Gupta M., Reddy V.R., Sharma G., Gupta A.

    Journal of Magnetism and Magnetic Materials   538   2021年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    In the present work, temperature dependent magnetic, structural and electronic properties of FeTa films with increasing Ta concentration are investigated. X-ray reflectivity (XRR) studies reveal densification of the film with increasing Ta concentration. Thermal annealing also results in an increased electron density relative to as-deposited film, concurrent with increase in grain size as observed from X-ray diffraction (XRD) and results of Soft-X-ray absorption spectroscopy (SXAS). However, grain growth is inhibited with increasing Ta concentration by presence of Ta in grain boundary (GB) region. This also results in increase in magnetic coercivity (greater than150 %) as observed from magneto-optical Kerr effect (MOKE). The structural properties were further correlated with magnetic properties as observed from Polarized neutron reflectivity (PNR) and Ferromagnetic resonance (FMR). Effective magnetic moment of the samples, as observed from PNR decreases with increasing Ta concentration and increases with increasing annealing temperature, which is in agreement with FMR results. Scattering length density profiles, observed from simultaneous fitting of XRR and PNR show presence of an oxide layer at surface, as also confirmed from SXAS measurements.

    DOI: 10.1016/j.jmmm.2021.168306

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  • Facet controlled anisotropic magnons in Y<inf>3</inf>Fe<inf>5</inf>O<inf>12</inf> thin films 査読有り 国際誌

    Medwal R., Deka A., Vas J.V., Duchamp M., Asada H., Gupta S., Fukuma Y., Rawat R.S.

    Applied Physics Letters   119 ( 16 )   2021年10月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Directional specific control on the generation and propagation of magnons is essential for designing future magnon-based logic and memory devices for low power computing. The epitaxy of the ferromagnetic thin film is expected to facilitate anisotropic linewidths, which depend on the crystal cut and the orientation of the thin film. Here, we have shown the growth-induced magneto-crystalline anisotropy in 40 nm epitaxial yttrium iron garnet (YIG) thin films, which facilitate cubic and uniaxial in-plane anisotropy in the resonance field and linewidth using ferromagnetic resonance measurements. The growth-induced cubic and non-cubic anisotropy in epitaxial YIG thin films are explained using the short-range ordering of the Fe3+ cation pairs in octahedral and tetrahedral sublattices with respect to the crystal growth directions. This site-preferred directional anisotropy enables an anisotropic magnon-magnon interaction and opens an avenue to precisely control the propagation of magnonic current for spin-transfer logics using YIG-based magnonic technology.

    DOI: 10.1063/5.0064653

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  • Pinning-assisted out-of-plane anisotropy in reverse stack FeCo/FePt intermetallic bilayers for controlled switching in spintronics 査読有り

    Vashisht G., Shashank U., Gupta S., Medwal R., Dong C.L., Chen C.L., Asokan K., Fukuma Y., Annapoorni S.

    Journal of Alloys and Compounds   877   2021年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    We study the implications of FeCo underlayer and overlayer on the static and dynamic magnetic properties of FeCo/FePt exchange spring system along with post-annealing kinetics. Probing of FePt/FeCo/Si and FeCo/FePt/Si bilayers using high energy synchrotron X-ray diffraction by varying glancing angles unveiled structural variations at the interface, where FeCo is observed to inhibit the crystalline growth of FePt. A soft ferromagnetic in-plane behavior and defect-driven hard ferromagnetic properties in the out-plane configuration are established. Besides, the magnetization dynamics studied by Ferromagnetic Resonance depicts an out-plane magnetization component of FePt only in FeCo/FePt/Si. X-ray Absorption Spectroscopy (XAS) in the Fe, Co and Pt L-edge regions reveal dissimilar interfaces in the two series due to thermal agitation effects. XAS spectra at Fe and Co K-edges ensure similar local coordination of Co immaterial of stack order, contrary to altered local geometry of Fe observed in the two series ascribed to varied crystallinity of FePt. Such structures are useful for spin-wave assisted low field magnetization switching in highly coercive FePt by using exchange coupled soft FeCo.

    DOI: 10.1016/j.jallcom.2021.160249

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  • Challenges and Applications to Operando and in Situ TEM Imaging and Spectroscopic Capabilities in a Cryogenic Temperature Range 査読有り

    Tyukalova E., Vimal Vas J., Ignatans R., Mueller A.D., Medwal R., Imamura M., Asada H., Fukuma Y., Rawat R.S., Tileli V., Duchamp M.

    Accounts of Chemical Research   54 ( 16 )   3125 - 3135   2021年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    ConspectusIn this Account, we describe the challenges and promising applications of transmission electron microscopy (TEM) imaging and spectroscopy at cryogenic temperatures. Our work focuses on two areas of application: the delay of electron-beam-induced degradation and following low-temperature phenomena in a continuous and variable temperature range. For the former, we present a study of LiMn1.5Ni0.5O4 lithium ion battery cathode material that undergoes electron beam-induced degradation when studied at room temperature by TEM. Cryogenic imaging reveals the true structure of LiMn1.5Ni0.5O4 nanoparticles in their discharged state. Improved stability under electron beam irradiation was confirmed by following the evolution of the O K-edge fine structure by electron energy-loss spectroscopy. Our results demonstrate that the effect of radiation damage on discharged LiMn1.5Ni0.5O4 was previously underestimated and that atomic-resolution imaging at cryogenic temperature has a potential to be generalized to most of the Li-based materials and beyond. For the latter, we present two studies in the imaging of low-temperature phenomena on the local scale, namely, the evolution of ferroelectric and ferromagnetic domains walls, in BaTiO3 and Y3Fe5O12 systems, respectively, in a continuous and variable temperature range. Continuous imaging of the phase transition in BaTiO3, a prototypical ferroelectric system, from the low-temperature orthorhombic phase continuously up to the centrosymmetric high-temperature phase is shown to be possible inside a TEM. Similarly, the propagation of domain walls in Y3Fe5O12, a magnetic insulator, is studied from ∼120 to ∼400 K and combined with the application of a magnetic field and electrical current pulses to mimic the operando conditions as in domain wall memory and logic devices for information technology. Such studies are promising for studying the pinning of the ferroelectric and magnetic domains versus temperature, spin-polarized current, and externally applied magnetic field to better manipulate the domain walls. The capability of combining operando TEM stimuli such as current, voltage, and/or magnetic field with in situ TEM imaging in a continuous cryogenic temperature range will allow the uncovering of fundamental phenomena on the nanometer scale. These studies were made possible using a MEMS-based TEM holder that allowed an electron-transparent sample to be transferred and electrically contacted on a MEMS chip. The six-contact double-tilt holder allows the alignment of the specimen into its zone axis while simultaneously using four electrical contacts to regulate the temperature and two contacts to apply the electrical stimuli, i.e., operando TEM imaging. This Account leads to the demonstration of (i) the high-resolution imaging and spectroscopy of nanoparticles oriented in the desired [110] zone-axis direction at cryogenic temperatures to mitigate the electron beam degradation, (ii) imaging of low-temperature transitions with accurate and continuous control of the temperature that allowed single-frame observation of the presence of both the orthorhombic and tetragonal phases in the BaTiO3 system, and (iii) magnetic domain wall propagation as a function of temperature, magnetic field, and current pulses (100 ns with a 100 kHz repetition rate) in the Y3Fe5O12 system.

    DOI: 10.1021/acs.accounts.1c00078

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  • Nonstoichiometric FePt Nanoclusters for Heated Dot Magnetic Recording Media 査読有り

    Mohan J.R., Medwal R., Gupta S., Gogia K., Vas J.V., Gupta R., Deka A., Rawat R.S., Subramanian A., Fukuma Y.

    ACS Applied Nano Materials   4 ( 7 )   7079 - 7085   2021年07月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Heated dot magnetic recording (HDMR) provides a path to increase the areal density of magnetic recording media beyond 4 Tb/in2. HDMR-based recording media requires ultrasmall, noninteracting, and thermally stable magnetic dots with high perpendicular anisotropy. We have synthesized nonstoichiometric Fe60Pt40nanoclusters with and without a Pt buffer layer on silicon substrates, which shows a reduction in chemical ordering temperatures. The Fe60Pt40nanoclusters retain the hard magnetic phase up to 1023 K with the coercive field of 1.3 Tesla due to the Pt element compensation from the buffer layer. This compensation of Pt was confirmed through X-ray diffraction (XRD) investigations where two distinct phases of Fe3Pt and FePt3are observed at elevated annealing temperatures. Micromagnetic simulations were performed to understand the effect of magnetic anisotropy, dipolar interaction, and exchange coupling between the soft magnetic Fe3Pt and hard magnetic FePt. The results imply that nonstoichiometric Fe60Pt40with the Pt buffer layer facilitates low chemical ordering temperatures retaining the high perpendicular anisotropy with minimal noninteracting behavior, suitable for HDMR.

    DOI: 10.1021/acsanm.1c01085

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  • Highly dose dependent damping-like spin-orbit torque efficiency in O-implanted Pt 査読有り

    Shashank U., Medwal R., Nakamura Y., Mohan J.R., Nongjai R., Kandasami A., Rawat R.S., Asada H., Gupta S., Fukuma Y.

    Applied Physics Letters   118 ( 25 )   2021年06月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Damping-like torque (DLT) arising from the spin Hall effect (SHE) in heavy metals and their alloys has been widely explored for applications in spin-orbit torque MRAM, auto-oscillations, spin waves, and domain wall motion. In conventional materials, the DLT efficiency is limited by intrinsic properties, while attaining strong spin-orbit coupling and higher spin-charge interconversion, with no compromise to electric properties, is the need of the hour. In this Letter, we report more than 3.5 times increase in DLT efficiency, θDL, of modified Pt-oxide by employing a better approach of low energy 20 keV O+ ion implantation. The highest fluence of O+ implantation (1 × 1017 ions cm−2) in Pt enhanced the DLT efficiency from 0.064 to 0.230 and improved the spin transmission for a smaller trade-off in the longitudinal resistivity (ρPt to ρPt−Oxide) from 55.4 to 159.5 μΩ cm, respectively. The transverse spin Hall resistivity, ρSH, is found to be proportional to the square of the longitudinal resistivity, i.e., ρSHimp∝ρimp2, implying that the enhanced SHE in O-implanted Pt is due to a side-jumping mechanism. Further, no break in the twofold as well as mirror symmetry of torques from the O-implanted Pt allows the use of spin-torque ferromagnetic resonance-based line shape analysis to quantify such torques.

    DOI: 10.1063/5.0054779

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  • Ultrafast Photo-Thermal Switching of Terahertz Spin Currents 査読有り

    Agarwal P., Medwal R., Kumar A., Asada H., Fukuma Y., Rawat R.S., Battiato M., Singh R.

    Advanced Functional Materials   31 ( 17 )   2021年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    Dissipationless and scattering-free spin-based terahertz electronics is the futuristic technology for energy-efficient information processing. Femtosecond light pulse provides an ideal pathway for exciting the ferromagnet (FM) out-of-equilibrium, causing ultrafast demagnetization and superdiffusive spin transport at sub-picosecond timescale, giving rise to transient terahertz radiation. Concomitantly, light pulses also deposit thermal energy at short timescales, suggesting the possibility of abrupt change in magnetic anisotropy of the FM that could cause ultrafast photo-thermal switching (PTS) of terahertz spin currents. Here, a single light pulse induced PTS of the terahertz spin current manifested through the phase reversal of the emitted terahertz photons is demonstrated. The switching of the transient spin current is due to the reversal of the magnetization state across the energy barrier of the FM layer. This demonstration opens a new paradigm for on-chip spintronic devices enabling ultralow-power hybrid electronics and photonics fueled by the interplay of charge, spin, thermal, and optical signals.

    DOI: 10.1002/adfm.202010453

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  • Enhanced Spin Hall Effect in S-Implanted Pt 査読有り

    Shashank U., Medwal R., Shibata T., Nongjai R., Vas J.V., Duchamp M., Asokan K., Rawat R.S., Asada H., Gupta S., Fukuma Y.

    Advanced Quantum Technologies   4 ( 1 )   2021年01月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    High efficiency of charge–spin interconversion in spin Hall materials is a prime necessity to apprehend intriguing functionalities of spin–orbit torque for magnetization switching, auto-oscillations, and domain wall motion in energy-efficient and high-speed spintronic devices. To this end, innovations in fabricating advanced materials that possess not only large charge–spin conversion efficiency but also viable electrical and spin Hall conductivity are of importance. Here, a new spin Hall material designed by implanting low energy 12 keV sulfur ions in heavy metal Pt, named as Pt(S), is reported that demonstrates eight times higher conversion efficiency as compared to pristine Pt. The figure of merit, spin Hall angle (θ ), up to (Formula presented.) of 0.502 together with considerable electrical conductivity (Formula presented.) of 1.65 × 10 Ω m is achieved. The spin Hall conductivity (Formula presented.) increases with increasing (Formula presented.), as (Formula presented.), implying an intrinsic mechanism in a dirty metal conduction regime. A comparatively large (Formula presented.) of 8.32 × 10 ((Formula presented.)) Ω m among the reported heavy-metals-based alloys can be useful for developing next-generation spintronic devices using spin–orbit torque. SH 6 –1 –1 5 –1 –1

    DOI: 10.1002/qute.202000112

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  • Magnetoimpedance of Epitaxial Y<inf>3</inf>Fe<inf>5</inf>O<inf>12</inf>(001) Thin Film in Low-Frequency Regime 査読有り

    Medwal R., Chaudhuri U., Vas J.V., Deka A., Gupta S., Duchamp M., Asada H., Fukuma Y., Mahendiran R., Rawat R.S.

    ACS Applied Materials and Interfaces   12 ( 37 )   41802 - 41809   2020年09月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    The atomically flat interface of the Y3Fe5O12 (YIG) thin film and the Gd3Ga5O12 (GGG) substrate plays a vital role in obtaining the magnetization dynamics of YIG below and above the anisotropy field. Here, magnetoimpedance (MI) is used to investigate the magnetization dynamics in fully epitaxial 45 nm YIG thin films grown on the GGG (001) substrates using a copper strip coil in the MHz-GHz frequency region. The resistance (R) and reactance (X), which are components of impedance (Z), allow us to probe the absorptive and dispersive components of the dynamic permeability, whereas a conventional spectrometer only measures the field derivative of the power absorbed. The distinct excitation modes arising from the resonance in the uniform and dragged magnetization states of YIG are respectively observed above and below the anisotropy field. The magnetodynamics clearly shows the visible dichotomy between two resonant fields below and above the anisotropy field and its motion as a function of the direction of the applied magnetic field. A low value of a damping factor of ∼4.7 - 6.1 × 10-4 is estimated for uniform excitation mode with an anisotropy field of 65 ± 2 Oe. Investigation of below and above anisotropy field-dependent magnetodynamics in the low-frequency mode can be useful in designing the YIG-based resonators, oscillators, filters, and magnonic devices.

    DOI: 10.1021/acsami.0c13213

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  • Modulation of Magnetization Precession Trajectories by Perpendicular Magnetic Anisotropy in CoFeB Thin Films 査読有り

    Deka A., Tanaka I., Mohan J.R., Fukuma Y.

    IEEE Transactions on Magnetics   56 ( 7 )   2020年07月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Precession trajectories during excitation of magnetization dynamics play an important role in determining spin wave propagation, emission power of spin torque oscillator, and spin current generated by spin pumping. However, comparatively little information has emerged on the effect of perpendicular magnetic anisotropy (PMA) on dynamical magnetization trajectories. The effect of PMA on magnetization dynamics has become particularly important since the discovery of voltage control of magnetic anisotropy in CoFeB/MgO junctions. This motivates us to investigate the effect of PMA on dynamical magnetization trajectories of CoFeB thin films using micromagnetic simulations. The ellipticity of the trajectories is found to increase monotonically with PMA. On the other hand, the area of such elliptical trajectories, which determine the spin current generation, shows a non-monotonous change with respect to PMA. This area can be expected to be maximum for the case where ellipticity is 0.5.

    DOI: 10.1109/TMAG.2020.2987288

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  • Electric-field control of interfacial in-plane magnetic anisotropy in CoFeB/MgO junctions 査読有り

    Deka A., Rana B., Anami R., Miura K., Takahashi H., Otani Y.C., Fukuma Y.

    Physical Review B   101 ( 17 )   2020年05月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    Magnetoelectric coupling in metal/oxide heterostructures has opened up the possibility of controlling magnetization by voltage, i.e., electric field. However, the electric-field excitation of magnetization dynamics in perfectly in-plane and out-of-plane magnetized films have not been demonstrated so far due to zero electric-field torque originating from voltage control of perpendicular magnetic anisotropy. This limits the application of voltage-controlled magnetic anisotropy in magnetic field free control of magnetization dynamics. Here we show that magnetic annealing can induce an interfacial in-plane magnetic anisotropy of CoFeB/MgO junctions, thereby controlling the symmetry of interfacial magnetic anisotropy. The magnetic anisotropy is modulated by applying voltage: a negative bias voltage increases perpendicular magnetic anisotropy, while a positive bias voltage decreases perpendicular magnetic anisotropy and increases the in-plane magnetic anisotropy. Such a control of symmetry of the interfacial magnetic anisotropy by magnetic annealing and its tunability by electric fields is useful for developing purely voltage-controlled spintronic devices.

    DOI: 10.1103/PhysRevB.101.174405

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  • Simulations on the Effect of Magnetic Anisotropy on Switching of an Easy Cone Magnetized Free Layer 査読有り

    Deka A., Sato K., Tanaka I., Fukuma Y.

    IEEE Transactions on Magnetics   56 ( 3 )   2020年03月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2020 IEEE. The easy cone state of magnetization that arises as a result of a competition between the second- A nd fourth-order perpendicular magnetic anisotropies has the advantage of a non-zero electric-field torque without the application of a bias magnetic field and is thus a potential candidate for purely voltage-driven magnetic storage devices. In this article, the onset of the easy cone state of magnetization is simulated in a ferromagnet film. Subsequently, the switching field and time for voltage-controlled magnetization switching process are studied as a function of the inclination angle of the easy cone state from the film normal in the range of 0°-45°. The switching field is found to decrease with decreasing anisotropy. The switching time is found to become faster for higher inclination angle of the easy cone state due to an increase in its torque.

    DOI: 10.1109/TMAG.2019.2942339

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  • Spin Pumping in Asymmetric Fe<inf>50</inf>Pt<inf>50</inf>/Cu/Fe<inf>20</inf>Ni<inf>80</inf> Trilayer Structure 査読有り 国際誌

    Medwal R., Gupta S., Rawat R., Subramanian A., Fukuma Y.

    Physica Status Solidi - Rapid Research Letters   2019年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim Herein, spin transport dynamics across asymmetric Fe50Pt50/Cu/Fe20Ni80 soft-magnetic trilayer structure is reported and thereby modulation of magnetic parameters including damping and effective field is determined by means of the angular dependence of broadband ferromagnetic resonance measurements. At distinct precession of individual magnetic layer, spin-pumping is found to be prevalent with expected linewidth increase. Mutual precession for wide range of resonance configuration reveals a collective reduction in anisotropy field of around 200 mT for both Fe50Pt50 and Fe20Ni80 systems. Subsequent observation of no-excess interface damping shows the possible control of spin-pumping effect by tuning the net flow of spin-current in a multilayer structure. These experimental findings have significance for microwave devices that require tunable anisotropy field in magnetic multilayers.

    DOI: 10.1002/pssr.201900267

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  • Spin Seebeck effect in neodymium iron garnet multilayers 査読有り

    Tyagi S., Maeda T., Kimura K., Gupta S., Kishimoto K., Koyanagi T., Asada H., Fukuma Y.

    Sensors and Materials   31 ( 8 )   2541 - 2546   2019年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © MYU K.K. Nanoscale sensing applications require significant power to operate, which can be largely supplied through the efficient management of omnipresent heat. The spin Seebeck effect (SSE) is rather a fresh energy harvesting phenomenon that enables the conversion of a temperature gradient across magnetic materials into spin current. This spin current can further be converted into charge current by adjoining heavy metals to the magnet. In this study, we fabricated the thermoelectric multilayer films of bismuth-substituted neodymium iron garnet (Nd2Bi1Fe5O12) (NIG) as well as gallium and bismuth co-substituted neodymium iron garnet (Nd2Bi1Fe4Ga1O12) (NIGG) on (111)-oriented gallium gadolinium garnet substrates by metal organic decomposition. The thicknesses of the NIG and NIGG multilayers are varied to control the magnetic properties. The observed spin Seebeck signal is found to be directly dependent on the garnet/heavy metal interface and tends to decrease in intensity with increasing amount of NIGG in the garnet multilayers. Our results emphasize the importance of magnet/ heavy metal interface properties for designing SSE-based sensors.

    DOI: 10.18494/SAM.2019.2335

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  • Effect of excitation power on voltage induced local magnetization dynamics in an ultrathin CoFeB film 査読有り

    Rana B., Fukuma Y., Miura K., Takahashi H., Otani Y.

    Scientific Reports   7 ( 1 )   2017年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2017 The Author(s). Voltage or electric field induced magnetization dynamics promises low power spintronics devices. For successful operation of some spintronics devices such as magnetic oscillators and magnetization switching devices a clear understanding of nonlinear magnetization dynamics is required. Here, we report a detailed experimental and micromagnetic simulation study about the effect of excitation power on voltage induced local magnetization dynamics in an ultrathin CoFeB film. Experimental results show that the resonance line-width and frequency remains constant, whereas cone angle of the magnetization precession increases linearly with square-root of excitation power below threshold value, known as linear excitation regime. Above threshold power, the dynamics enters into nonlinear regime where resonance line-width monotonically increases and resonance frequency monotonically decreases with increasing excitation power. Simulation results reveal that a strong nonlinear and incoherent magnetization dynamics are observed in our experiment above the threshold power which reduces dynamic magnetic signal by suppressing large cone angle of magnetization precession. Moreover, a significant transfer of spin angular momentum from uniform FMR mode to its degenerate spin waves outside of excitation area further restrict the cone angle of precession within only few degrees in our device. Our results will be very useful to develop all-voltage-controlled spintronics devices.

    DOI: 10.1038/s41598-017-02427-3

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  • Excitation of coherent propagating spin waves in ultrathin CoFeB film by voltage-controlled magnetic anisotropy 査読有り

    Rana B., Fukuma Y., Miura K., Takahashi H., Otani Y.

    Applied Physics Letters   111 ( 5 )   2017年07月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2017 Author(s). Spin waves (SWs) may be used as potential information carriers in next generation low-power spintronics devices. Here, we report an experimental study on the excitation of propagating magnetostatic surface SWs by voltage-controlled magnetic anisotropy in a 2 nm thick CoFeB film. The SWs are detected by a pico-second time-resolved longitudinal Kerr microscope with a spatial resolution of 600 nm. We found a linear increase in the SW amplitude with the applied rf voltage. We show that in this ultrathin film, the voltage excited SWs can propagate up to micrometer distances which decrease with the increase in the bias magnetic field value. This is also supported by micromagnetic simulation results. Furthermore, we show that voltage excitations are spatially localized as opposed to conventional microstrip antenna induced Oersted field excitations. We discuss about the advantage of voltage excitation compared to the Oersted field excitation. We believe that voltage excitation of SWs will be more suitable and useful for the development of all-voltage-controlled nanoscale spintronics devices with a high density of integration.

    DOI: 10.1063/1.4990724

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  • Voltage-induced magnetization dynamics in CoFeB/MgO/CoFeB magnetic tunnel junctions 査読有り

    Miura K., Yabuuchi S., Yamada M., Ichimura M., Rana B., Ogawa S., Takahashi H., Fukuma Y., Otani Y.

    Scientific Reports   7   2017年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © The Author(s) 2017. Recent progress in magnetic tunnel junctions (MTJs) with a perpendicular easy axis consisting of CoFeB and MgO stacking structures has shown that magnetization dynamics are induced due to voltage-controlled magnetic anisotropy (VCMA), which will potentially lead to future low-power-consumption information technology. For manipulating magnetizations in MTJs by applying voltage, it is necessary to understand the coupled magnetization motion of two magnetic (recording and reference) layers. In this report, we focus on the magnetization motion of two magnetic layers in MTJs consisting of top layers with an in-plane easy axis and bottom layers with a perpendicular easy axis, both having perpendicular magnetic anisotropy. According to rectified voltage (V rec ) measurements, the amplitude of the magnetization motion depends on the initial angles of the magnetizations with respect to the VCMA direction. Our numerical simulations involving the micromagnetic method based on the Landau-Lifshitz-Gilbert equation of motion indicate that the magnetization motion in both layers is induced by a combination of VCMA and transferred angular momentum, even though the magnetic easy axes of the two layers are different. Our study will lead to the development of voltage-controlled MTJs having perpendicular magnetic anisotropy by controlling the initial angle between magnetizations and VCMA directions.

    DOI: 10.1038/srep42511

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  • Important role of magnetization precession angle measurement in inverse spin Hall effect induced by spin pumping 査読有り

    Gupta S., Medwal R., Kodama D., Kondou K., Otani Y., Fukuma Y.

    Applied Physics Letters   110 ( 2 )   2017年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2017 Author(s). Here, we investigate the spin Hall angle of Pt in a Ni 80 Fe 20 /Pt bilayer system by using a broadband spin pumping and inverse spin Hall effect measurement. An out-of-plane excitation geometry with an application of external magnetic field perpendicular to the charge current direction is utilized in order to suppress unwanted galvanomagnetic effects. Magnetization precession angle (θ C ) on ferromagnetic resonance for wide excitation frequency range (4-14 GHz) is estimated from the rectification voltage of anisotropic magnetoresistance (AMR) and a conventional method of using the microwave power in a coplanar waveguide. A marked difference in θ C profiles for the different methods is observed, resulting in the large variation in estimated values of spin current density at Ni 80 Fe 20 /Pt interface. The frequency dependence of the spin current density estimated using the AMR effect is found to be similar to that of the inverse spin Hall voltage. We obtain the frequency-invariant spin Hall angle of 0.067 ± 0.002.

    DOI: 10.1063/1.4973704

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  • Fermi-level-dependent charge-to-spin current conversion by Dirac surface states of topological insulators 査読有り

    Kondou K., Yoshimi R., Tsukazaki A., Fukuma Y., Matsuno J., Takahashi K., Kawasaki M., Tokura Y., Otani Y.

    Nature Physics   12 ( 11 )   1027 - 1031   2016年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2016 Macmillan Publishers Limited. All rights reserved. Spin-momentum locking in the Dirac surface state of a topological insulator (TI) offers a distinct possibility for highly efficient charge-to-spin current (C-S) conversion compared with spin Hall effects in conventional paramagnetic metals. For the development of TI-based spin current devices, it is essential to evaluate this conversion efficiency quantitatively as a function of the Fermi level position E F. Here we introduce a coefficient q ICS to characterize the interface C-S conversion effect by means of the spin torque f erromagnetic resonance (ST-FMR) for (Bi 1'x Sb x) 2 Te 3 thin films as E F is tuned across the bandgap. In bulk insulating conditions, the interface C-S conversion effect via the Dirac surface state is evaluated as having large, nearly constant values of q ICS, reflecting that q ICS is inversely proportional to the Fermi velocity v F, which is almost constant. However, when E F traverses through the Dirac point, the q ICS is remarkably reduced, possibly due to inhomogeneity of k F and/or instability of the helical spin structure. These results demonstrate that fine tuning of E F in TI-based heterostructures is critical in maximizing the efficiency using the spin-momentum locking mechanism.

    DOI: 10.1038/nphys3833

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  • Epitaxial growth of diluted magnetic semiconductor Ge<inf>1-x</inf>Cr<inf>x</inf>Te with high Cr composition 査読有り

    Fukuma Y., Asada H., Senba S., Koyanagi T.

    Applied Physics Letters   108 ( 22 )   2016年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    © 2016 Author(s). IV-VI diluted magnetic semiconductor Ge 1-x Cr x Te layers up to x = 0.1 were grown on SrF 2 substrates by molecular beam epitaxy. In situ reflection high-energy electron diffraction shows a streaky pattern with a sixfold symmetry in the plane for the Ge 1-x Cr x Te layer, implying an epitaxial growth of Ge 1-x Cr x Te (111)/SrF 2 (111). A clear hysteresis loop is observed in the anomalous Hall effect measurements due to the strong spin-orbit interaction in the host GeTe. The Curie temperature increases with increasing Cr composition up to 200 K, but there is no clear dependence of the Curie temperature on the hole concentration, implying that the mechanism of the ferromagnetic interaction among Cr ions is different from Mn doped diluted magnetic semiconductors.

    DOI: 10.1063/1.4953042

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=84974569609&origin=inward

  • Spin relaxation characteristics in Ag nanowire covered with various oxides 査読有り

    S. Karube, H. Idzuchi, K. Kondou, Y. Fukuma, Y. Otani

    Applied Physics Letters   107 ( 122406 )   1 - 5   2015年09月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4931697

    Scopus

  • Spin transport in non-magnetic nano-stuructures induced by non-local spin injection 招待有り 査読有り

    H. Idzuchi, Y. Fukuma, Y. Otani

    Physica E   68   239 - 263   2015年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1016/j.physe.2014.11.023

    Scopus

  • Critical exponents and domain structures of magnetic semiconductor EuS and Gd-doped EuS films near Curie temperature 査読有り

    H. Idzuchi, Y. Fukuma, H. S. Park, T. Matsuda, T. Tanigaki, S. Aizawa, M. Shirai, D. Shindo, Y. Otani

    Applied Physics Express   7 ( 113002 )   1 - 4   2014年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.7567/APEX.7.113002

    Scopus

  • Effect of anisotropic spin absorption on the Hanle effect in lateral spin valves 査読有り

    H. Idzuchi, Y. Fukuma, S. Takahashi, S. Maekawa, and Y. Otani

    Physical Review B (Rapid Communication)   89   081308 - 081312   2014年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1103/PhysRevB.89.081308

    Scopus

  • Coherency of spin precession in metallic lateral spin valves

    YoshiChika Otani, Hiroshi Idzuchi, Yasuhiro Fukuma

    In memory of Akira Tonomura ( World Scientific )   2014年01月

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    記述言語:英語   掲載種別:記事・総説・解説・論説等(商業誌、新聞、ウェブメディア)

  • Detection of a symmetric circular gyration of the vortex core via the second-order harmonic magnetoresistance oscillation 査読有り

    S. Sugimoto, N. Hasegawa, Y. Niimi, Y. Fukuma, S. Kasai, and Y. Otani

    Applied Physics Express   7   023006 - 023009   2014年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.7567/APEX.7.023006

    Scopus

  • 5d iridium oxide as a material for spin-current detection 査読有り

    K. Fujiwara, Y. Fukuma, J. Matsuno, H. Idzuchi, Y. Niimi, Y. Otani, and H. Takagi

    Nature Communications   4   2893 - 2898   2013年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1038/ncomms3893

    Scopus

  • Impact of interface properties on spin accumulation in dual-injection lateral spin valves 査読有り

    H. Idzuchi, S. Karube, Y. Fukuma, T. Aoki, and Y. Otani

    Applied Physics Letters   103   162403 - 162406   2013年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4824897

    Scopus

  • Configurational anisotropic spin waves in cross-shaped Ni80Fe20 nanoelements 査読有り

    B. K. Mahato, B. Rana, R. Mandal, D. Kumar, S. Barman, Y. Fukuma, Y. Otani, A. Barman

    Applied Physics Letters   102 ( 192402 )   1 - 4   2013年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4804990

    Scopus

  • Tunable Magnonic Spectra in Two-Dimensional Magnonic Crystals with Variable Lattice Symmetry 査読有り

    S. Saha, R. Mandal, S. Barman, D. Kumar, B. Rana, Y. Fukuma, S. Sugimoto, Y. Otani, A. Barman

    Advanced Functional Materials   23 ( 19 )   2378 - 2386   2013年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1002/adfm.201202545

    Scopus

  • スピントロニクス技術を用いた高感度磁気センサー開発の動向

    福間康裕、大谷義近

    研究開発リーダー ( 株式会社技術情報協会 )   2013年04月

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    担当区分:責任著者   記述言語:日本語   掲載種別:記事・総説・解説・論説等(商業誌、新聞、ウェブメディア)

  • Spin injection properties in trilayer graphene lateral spin valves 査読有り

    Y. P. Liu, H. Idzuchi, Y. Fukuma, O. Rousseau, Y. Otani and W. S. Lew

    Applied Physics Letters   2013年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4776699

    Scopus

  • Towards coherent spin precession in pure-spin current 査読有り

    H. Idzuchi, Y. Fukuma, and Y. Otani

    Scientific Reports   2 ( 628 )   1 - 5   2012年09月

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    担当区分:責任著者   記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1038/srep00628

    Scopus

  • Spin relaxation mechanism in silver nanowires covered with MgO protection layer 査読有り

    H. Idzuchi, Y. Fukuma, L. Wang, and Y. Otani

    Applied Physics Letters   101 ( 022415 )   1 - 4   2012年07月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.4737001

    Scopus

  • Optically Induced Tunable Magnetization Dynamics in Nanoscale Co Antidot Lattices 査読有り

    R. Mandal, S. Saha, D. Kumar, S. Barman, S. Pal, K. Das, A. Raychaudhuri, Y. Fukuma, Y. Otani, and A. Barman

    ACS NANO   6   3397 - 3403   2012年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1021/nn300421c

    Scopus

  • Temperature evolution of spin-polarized electron tunneling in Silicon nanowire-Permalloy lateral spin valve system 査読有り

    J. Tarun, S. Huang, Y. Fukuma, H. Idzuchi, Y. Otani, N. Fukata, K. Ishibashi, and S. Oda

    Applied Physics Express   5   045001   2012年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Anisotropy in collective precessional dynamics in arrays of Ni80Fe20 nanoelements 査読有り

    B. Rana, D. Kumar, S. Barman, S. Pal, R. Mandal, Y. Fukuma, Y. Otani, S. Sugimoto, and A. Barman

    Journal of Applied Physics   111   07D503   2012年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.3672402

    Scopus

  • Manipulation of the excitation state of the coupled vortices in a pair of magnetic disks 査読有り

    S. Sugimoto,Y. Fukuma, and Y. Otani

    IEEE Transactions on Magnetics   47   2951   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1109/TMAG.2011.2159367

    Scopus

  • All-optical excitation and detection of picosecond dynamics of ordered arrays of nanomagnets with varying areal density 査読有り

    B. Rana, S. Pal, S. Barman, Y. Fukuma, Y. Otani, and A. Barman

    Applied Physics Express   4   113003   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1143/APEX.4.113003

    Scopus

  • Detection of picosecond magnetization dynamics of 50 nm magnetic dots down to the single dot regime 査読有り

    B. Rana, D. Kumar, S. Barman, S. Pal, Y. Fukuma, Y. Otani, and A. Barman

    ACS nano   5   9559   2011年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1021/nn202791g

    Scopus

  • Effect of annealing on interfacial spin polarization and resistance in Permalloy/MgO/Ag lateral spin valves 査読有り

    L. Wang, Y. Fukuma, H.Idzuchi, G. Yu, Y. Jiang, and Y. Otani

    Applied Physics Express   4   093004   2011年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1143/APEX.4.093004

    Scopus

  • Spin injection into magnesium nanowire 査読有り

    H. Idzuchi, Y. Fukuma, L. Wang, and Y. Otani

    IEEE Transactions on Magnetics   47   1545   2011年06月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1109/TMAG.2011.2108272

    Scopus

  • Giant enhancement of spin accumulation and long-distance spin precession in metallic lateral spin valves 査読有り

    Y. Fukuma, L. Wang, H. Idzuchi, S. Takahashi, S. Maekawa, and Y. Otani

    Nature Materials   10   527   2011年06月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1038/nmat3046

    Scopus

  • Dynamics of coupled vortices in a pair of ferromagnetic disks 査読有り

    S. Sugimoto, Y. Fukuma, S. Kasai, T. Kimura, A. Barman, and Y. Otani

    Physical Review Letters   106   197203   2011年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1103/PhysRevLett.106.197203

    Scopus

  • Optical detection of spin transport in nonmagnetic metals 査読有り

    F. Fohr, S. Kaltenborn, J. Hamrle, H. Schultheib, A.A. Serga, H.C. Schneider, B. Hillebrands, Y. Fukuma, L. Wang, and Y. Otani

    Physical Review Letters   106   226601   2011年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1103/PhysRevLett.106.226601

    Scopus

  • Efficient spin injection into nonmagnetic metals through low-resistance MgO 査読有り

    L. Wang, Y. Fukuma, H. Idzuchi Y. Otani

    Journal of Applied Physics   109   07C506   2011年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.3556759

    Scopus

  • Demonstration of spin valve effects in silicon nanowires 査読有り

    J. Tarun, S. Huang, Y. Fukuma, H. Idzuchi, Y. Otani, N. Fukata, K. Ishibashi S. Oda

    Journal of Applied Physics   109   07C208   2011年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.3562904

    Scopus

  • Gyration mode splitting in magnetostatically coupled magnetic vortices in an array 査読有り

    A. Barman, S. Barman, T. Kimura, Y. Fukuma Y. Otani

    Journal of Physics D: Appied Physics   43   422001   2010年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1088/0022-3727/43/42/422001

    Scopus

  • Enhanced spin accumulation obtained by inserting low-resistance MgO interface in metallic lateral spin 査読有り

    Y. Fukuma, L. Wang, H. Idzuchi Y. Otani

    Applied Physics Letters   97   012507   2010年07月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1063/1.3460909

    Scopus

  • Spin diffusion characteristics in magnesium nanowires 査読有り

    H. Idzuchi, Y. Fukuma, L. Wang, Y. Otani

    Applied Physics Express   3   063002   2010年05月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

    DOI: 10.1143/APEX.3.063002

    Scopus

  • Strong uniaxial magnetic anisotropy in CoFe films on obliquely sputtered Ru underlayer 査読有り

    Y. Fukuma, Z. Lu, H. Fujiwara, G. J. Mankey, W. H. Butler, and S. Matsunuma

    Journal of Applied Physics   106   76101   2009年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Magnetic anisotropy of FeCo films induced by obliquely sputtered Ru underlayers 査読有り

    Z. Lu, Y. Fukuma, W. H. Butler, H. Fujiwara, G. J. Mankey, and S. Matsunuma

    IEEE Transactions on Magnetics   45   4008   2009年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Coherent suppression of magnetization precession in presence of spin waves in NiFe microwire 査読有り

    A. Barman, T. Kimura, Y. Fukuma, and Y. Otani

    IEEE Transactions on Magnetics   45   4104   2009年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Coherent suppression of picosecond magnetization precession in the presence of spin waves in a NiFe 査読有り

    A. Barman, H. Sakata, T. Kimura, Y. Otani, and Y. Fukuma

    Journal of Applied Physics   106   43906   2009年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Trimmed-diamond shaped toggle magnetoresistive random access memory cells 査読有り

    Y. Fukuma, H. Fujiwara, P. B. Visscher, and G. J. Mankey

    Journal of Applied Physics   105   73916   2009年04月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Benchtop time-resolved magneto-optical Kerr magnetometer 査読有り

    A. Barman, T. Kimura, Y. Otani, Y. Fukuma, K. Akahane, and S. Meguro

    Review of Scientific Instruments   79   123905   2008年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Carrier-induced ferromagnetism in Ge0.92Mn0.08Te epilayers with a Curie temperature up to 190K 査読有り

    Y. Fukuma, H. Asada, S. Miyawaki, T. Koyanagi, S. Senba, K. Goto, and H. Sato

    Applied Physics Letters   93   252502   2008年12月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Preparation of (Ge1-yPby)1-xMnxTe thin films and their magnetic properties 査読有り

    H. Asada, Y. Fukuma, D. Kitabori, A. Ooji, Y. Kamimoto and T. Koyanagi

    IEEE Transactions on Magnetics   44   2696   2008年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Large magnetic circular dichroism of Co clusters in Co-doped ZnO 査読有り

    Y. Fukuma, H. Asada, J. Yamamoto, F. Odawara, and T. Koyanagi

    Applied Physics Letters   93   142510   2008年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Effects of annealing and chemical doping on magnetic properties in Co-doped ZnO films 査読有り

    Y. Fukuma, F. Odawara, H. Asada, and T. Koyanagi

    Physical Review B   78   104417   2008年09月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • IV-VI diluted magneic semiconductor Ge1-xMnxTe epilayer grown by molecular beam epitaxy 査読有り

    Y. Fukuma, K. Goto, S. Senba, S. Miyawaki, H. Asada, T. Koyanagi, and H. Sato

    Journal of Applied Physics   103   53904   2008年03月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Toggle switching of weakly coupled synthetic antiferromagnet for high-density mognetoresistive random 査読有り

    Y. Fukuma, H. Fujiwara, and P. B. Visscher

    Journal of Applied Physics   103   07A716   2008年02月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Long-range ferromagnetic interaction in Ge1-xMnxTe with high x 査読有り

    Y. Fukuma, K. Tanaka, H. Asada, and T. Koyanagi

    Journal of Magnetism and Magnetic Materials   310   e723   2007年11月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Ferromagnetic semiconductor Ge1-xCrxTe with a Curie temperature of 180K 査読有り

    Y. Fukuma, H. Asada, N. Moritake, T. Irisa, and T. Koyanagi

    Applied Physics Letters   91   92501   2007年08月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Ferromagnetism in Ge1-xCrxTe epilayers grown by molecular beam epitaxy 査読有り

    Y. Fukuma, T. Taya, T. Irisa, H. Asada, and T. Koyanagi

    Applied Physics Letters   89   152506   2006年10月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Local environment of Mn atoms in IV-VI ferromagnetic semiconductor Ge1-xMnxTe 査読有り

    Y. Fukuma, H. Sato, K. Fujimoto, K. Tsuji, A. Kimura, M. Taniguchi, S. Senba, A. Tanaka, H. Asada, and T. Koyanagi

    Journal of Applied Physics   99   08D510   2006年06月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Growth and magnetic properties of IV-VI diluted magnetic semiconductor Ge1-xCrxTe 査読有り

    Y. Fukuma, T. Taya, S. Miyawaki, T. Irisa, H. Asada, and T. Koyanagi

    Journal of Applied Physics   99   08D508   2006年06月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

  • Ferromagnetic order in GeCrTe 査読有り

    Y. Fukuma, H. Asada, and T. Koyanagi

    Applied Physics Letters   88   32507   2006年01月

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    記述言語:英語   掲載種別:研究論文(学術雑誌)

▼全件表示

口頭発表・ポスター発表等

  • Information processing capacity of dipolar coupled spin Hall oscillators

    J. R. Mohan, C. Yamanaka, R. Feng, Y. Hasunaka, Y. Fukuma

    The 5th International Symposium on Neuromorphic AI Hardware 

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    開催期間: 2024年03月   記述言語:英語   開催地:kitakyushu  

    その他リンク: https://www.brain.kyutech.ac.jp/~neuro/2023/11/30/5th-sympo/?lang=en

  • Six-bit classification using magnetostatically coupled spin Hall oscillators

    Y. Hasunaka, J.R. Mohan, C. Yamanaka, R. Feng, Y. Fukuma

    The 5th International Symposium on Neuromorphic AI Hardware 

     詳細を見る

    開催期間: 2024年03月   記述言語:英語   開催地:kitakyushu  

    その他リンク: https://www.brain.kyutech.ac.jp/~neuro/2023/11/30/5th-sympo/?lang=en

  • Evaluation of memory capacity of magnetic vortex oscillator

    R. Feng, J.R. Mohan, Y. Fukuma

    The 5th International Symposium on Neuromorphic AI Hardware 

     詳細を見る

    開催期間: 2024年03月   記述言語:英語   開催地:kitakyushu  

    その他リンク: https://www.brain.kyutech.ac.jp/~neuro/2023/11/30/5th-sympo/?lang=en

  • Efficacy of ion implantation in Pt for controllable enhancement of spin Hall angle

    G. Garima, K. Imai, Y. Kusaba, K. Asokan, H. Asada, Y. Fukuma

    21st International conference on Radiation effects in insulators 

     詳細を見る

    開催期間: 2023年09月   記述言語:英語   開催地:Fukuoka  

    その他リンク: https://rei21.kyushu-u.ac.jp/

  • Electric Field Mediated Strain Control of Terahertz Spin Current Pulse

    A. CHAURASIYA, Z. LI, R. MEDWAL (Indian Institute of Technology Kanpur), Surbhi GUPTA, John Rex MOHAN, Yosuhiro FUKUMA, Hironori ASADA, Elbert CHIA, Rajdeeep Singh RAWAT (Nanyang Technological University)

    11th internationa conference on Materials for advanced technoloies, IUMRS-ICAM & ICMAT 2023 

     詳細を見る

    開催期間: 2023年06月   記述言語:英語   開催地:Singapore  

    その他リンク: https://www.icmat2023.mrs.org.sg/public.asp?page=program_overview.asp

  • Anisotropy Assisted Bias-free Spin Hall Nano Oscillator

    S. MANNA, R. MEDWAL (Indian Institute of Technology Kanpur), S. GUPTA, J. R. MOHAN, Y. FUKUMA, R. S. RAWAT (Nanyang Technological University)

    11th internationa conference on Materials for advanced technoloies, IUMRS-ICAM & ICMAT 2023 

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    開催期間: 2023年06月   記述言語:英語   開催地:Singapore  

    その他リンク: https://www.icmat2023.mrs.org.sg/public.asp?page=program_overview.asp

  • Chirality Controlled Broadband Spintronic Terahertz Emitter

    P. AGARWAL, R. MEDWAL (Indian Institute of Technology Kanpur), J. R. MOHAN, S. S. MISHRA, H. ASADA, Y. FUKUMA, R. SINGH (Nanyang Technological University)

    11th internationa conference on Materials for advanced technoloies, IUMRS-ICAM & ICMAT 2023 

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    開催期間: 2023年06月   記述言語:英語   開催地:Singapore  

    その他リンク: https://www.icmat2023.mrs.org.sg/public.asp?page=program_overview.asp

  • Spin Hall Effect in Se-implanted Pt from Extrinsic Scattering

    G. Vashisht, U. Shashank, Y. Kusaba, T. Tomoda, R. Nongjai, P. Murmu, J. Kennedy, R. Medwal (Indian Institute of Technology Kanpur), S. Gupta, R. Rawat (Nanyang Technological University), A. Kandasami, H. Asada, Y. Fukuma

    Intermag 2023 

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    開催期間: 2023年05月   記述言語:英語   開催地:Sendai  

    その他リンク: https://2023.intermag.org/

  • Modelling in-device inference and classification of binary digits using nonlinear dynamics of spin Hall oscillator

    J.R. Mohan, C. Yamanaka, R. Feng, A. Mathew, Y. Nakamura, R. Medwal (Indian Institute of Technology Kanpur), S. Gupta, R. Rawat (Nanyang Technological University), Y. Fukuma

    Intermag 2023 

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    開催期間: 2023年05月   記述言語:英語   開催地:Sendai  

    その他リンク: https://2023.intermag.org/

  • リンイオンを注入した白金薄膜のスピンホール効果

    友田好郁、シャシャンクウトカッシュ、草場優、堀部陽一、石丸学、浅田裕法、福間康裕

    第70回応用物理学会 春季学術講演会 

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    開催期間: 2023年03月18日   記述言語:日本語  

  • イオン注入した白金薄膜の外因性スピンホール効果

    草場優, シャシャンクウトカッシュ, ノンジャイラジア, ムルムピーター, ケネディージョン, カンダサミー アソカン, メドワルロヒット, グプタスルビ, ラジディープラワット , 福間康裕

    第70回応用物理学会 春季学術講演会 

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    開催期間: 2023年03月15日   記述言語:日本語  

  • Unraveling the charge-to-spin conversion from 2DEGs at SrTiO3 based interfaces

    U. Shashank, A. Deka, C. Ye, S. Gupta, R. Medwal, R. S. Rawat, H. Asada, X. R. Wang, Y. Fukuma

    APS March Meeting 2023 

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    開催期間: 2023年03月06日   記述言語:英語  

  • Reservoir computing with spin Hall oscillators at easy-cone state

    R. Feng, C. Yamanaka, J. R. Mohan, A. J. Mathew, Y. Fukuma

    4th international symposium on neuromorphic AI hardware 

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    開催期間: 2022年12月14日   記述言語:英語  

  • Nonlinear dynamics of time dependent RF pumping in SOT devices for neuromorphic computing

    Y. Nakamura, J. R. Mohan, R. Feng, C. Yamanaka, Y. Fukuma

    4th international symposium on neuromorphic AI hardware 

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    開催期間: 2022年12月14日   記述言語:英語  

  • Intrinsic-extrinsic crossover of spin Hall effect in O and N-implanted Pt

    U. Shashank, Y. Kusaba, Y. Nakamura, T. Tomoda, R. Nongjai, A. Kandasami, R. Medwal, R. S. Rawat, H. Asada, S. Gupta, Y. Fukuma

    Ion Beams in Materials Engineering and Characterization IBMEC 2022 

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    開催期間: 2022年11月16日   記述言語:英語  

  • Engineering spin Hall effect by ion implantation 招待有り

    Y. Fukuma

    Ion Beams in Materials Engineering and Characterization IBMEC 2022 

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    開催期間: 2022年11月16日   記述言語:英語  

  • Generation of Magnons with Nanoscale Wavelengths using Voltage Controlled Parametric Resonance

    A. Deka, B. Rana, R. Anami, K. Miura, H. Takahashi, Y.C. Otani, Y. Fukuma

    MMM 2022 Conference 

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    開催期間: 2022年11月02日   記述言語:英語  

  • Spin Hall materials fabricated by ion implantation in platinum 招待有り

    Y. Fukuma

    Workshop on spin orbit torque materilas and devices 

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    開催期間: 2022年07月28日   記述言語:英語  

  • Evaluation of memory capacity of spin Hall oscillator for physical reservoir computing

    A. J. Mathew, J. R. Mohan, R. Feng, Y. Nakamura, R. Medwal, S. Gupta, R. S. Rawat, Y. Fukuma

    The 3rd international symposium on neuromorphic AI hardware 

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    開催期間: 2022年03月18日 - 2022年03月19日   記述言語:英語  

  • Classification tasks using input driven nonlinear magnetization dynamics in spin Hall oscillator

    J. R. Mohan, A. J. Mathew, K. Nishimura, R. Feng, Y. Nakamura, R. Medwal, S. Gupta, R. S. Rawat, Y. Fukuma

    The 3rd international symposium on neuromorphic AI hardware 

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    開催期間: 2022年03月18日 - 2022年03月19日   記述言語:英語  

  • Enhancement of spin Hall effect in O-implanted Pt by side-jump scattering

    U. Shashank, R. Medwal, Y. Nakamura, J. R. Mohan, R. Nongjai, K. Asokan, R. S. Rawat, H. Asada, S. Gupta, Y. Fukuma

    APS March Meeting 2022 

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    開催期間: 2022年03月12日 - 2022年03月18日   記述言語:英語  

  • OPTICAL HEATING MEDIATED RECONFIGURABLE TERAHERTZ SPINTRONIC EMITTERS

    P. Agarwal, R. Medwal, A. Kumar, R. S. Rawat, M. Battiato, R. Singh , H. Asada, Y. Fukuma

    47th IEEE International conference on Plasma Sciences and 2nd Asia-Pacific conference on Plasma and Terahertz Science 

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    開催期間: 2020年12月06日 - 2020年12月10日   記述言語:英語  

  • Voltage controlled magnetization dynamics of NiFe on PMN-PT single crystal

    M. J. Rex, K. Ushima, S. Gupta, Y. Fukuma, R .S. Rawat, R. Medwal

    47th IEEE International conference on Plasma Sciences and 2nd Asia-Pacific conference on Plasma and Terahertz Science 

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    開催期間: 2020年12月06日 - 2020年12月10日   記述言語:英語  

  • Spin-transport study in SrTiO based two-dimensional electron gas created by argon ions

    U. Shashank, S. Gupta, Y. Fukuma, H. Asada, Y. Chen, X. R. Wang, R. Medwal, R. S. Rawat

    47th IEEE International conference on Plasma Sciences and 2nd Asia-Pacific conference on Plasma and Terahertz Science 

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    開催期間: 2020年12月06日 - 2020年12月10日   記述言語:英語  

  • Unusual Electronic Transport Properties of Sputter-Deposited Co25Fe75 /Pt Based Heterostructured Thin Film Sample

    H. Saren, Y. Kumar, A. Deka, Y. Fukuma, H. Asada, P. Das

    65th annual conference on Magnetic and Magnetic Materials 

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    開催期間: 2020年12月02日 - 2020年12月06日   記述言語:英語  

  • Thickness dependent interfacial spin orbit torques in NiFe/Pt bilayers

    M. John Rex, U. Shashank, A. Deka, R. Medwal, S. Gupta, R. S. Rawat, H. Asada, Y. Fukuma

    5th International conference on Emerging Electronics  IEEE

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    開催期間: 2020年11月26日 - 2020年11月28日   記述言語:英語   開催地:virtual  

  • High charge-to-spin interconversion in Sulphur implanted Platinum

    U. Shashank, R. Medwal, T. Shibata, R. Nongjai, J. V. Vas, M. Duchamp, K. Asokan, R. S. Rawat, H. Asada, S. Gupta, Y. Fukuma

    5th International conference on Emerging Electronics  IEEE

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    開催期間: 2020年11月26日 - 2020年11月28日   記述言語:英語   開催地:virtual  

  • Electric-field induced spin pumping in an in-plane magnetized CoFeB/MgO junction

    A. Deka, B. Rana, R. Anami, K. Miura, H. Takahashi, Y.C. Otani, Y. Fukuma

    64th annual conference on Magnetic and Magnetic Materials 

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    開催期間: 2019年11月04日 - 2019年11月08日   記述言語:英語  

  • Effect of perpendicular magnetic anisotropy in voltage induced magnetization switching

    A. Deka, I. Tanaka, K. Sato, Y. Fukuma

    The 30th Magnetic Recording Conference 

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    開催期間: 2019年07月08日 - 2019年07月10日   記述言語:英語  

  • Investigation of spin transport properties in IrMn/Py heterostructures

    Akash Kumar, Niru Chowdhury, Kacho Imtiyaz Ali Khan, Raghav Sharma, Shashank Tyagi, Yasuhiro Fukuma, Pranaba Kishor Muduli

    10th International Conference on Materials for Advanced Technologies 

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    開催期間: 2019年06月23日 - 2019年06月28日   記述言語:英語  

  • Enhancement of spin-orbit-torque by introducing S+ impurities in Pt

    U. Shashank, R. Medwal, S. Gupta, R. Nongjai, M. Bala, R. S. Rawat, K. Asokan, H. Asada, Y. Fukuma

    6th international symposium on appled engineering and sciences 

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    開催期間: 2018年12月15日   記述言語:英語  

  • Micromagnetic Simulation study of Exchange interaction of off stoichiometric FePt/Pt bilayers

    M. John Rex, R. Medwal, S. Gupta, R. S. Rawat, S. Annapoorni, Y. Fukuma

    6th international symposium on appled engineering and sciences 

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    開催期間: 2018年12月15日   記述言語:英語  

  • In search of Magnetic Skyrmion in Co25Fe75 based Thin Film heterostructure

    Hurmal Saren, Angshuman Deka, Yasuhiro Fukuma, Hironori Asada, Pintu Das

    International conference on magnetic materials and applications 

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    開催期間: 2018年12月09日 - 2018年12月13日   記述言語:英語  

  • Spin-orbit interaction modulation induced by Sulphur and Oxygen implantation in Pt thin film

    T. Shibata, S. Gupta, R. Medwal, R. Nongzai, R. S. Rawat, K. Asokan, H. Asada, Y. Fukuma

    5th international conference on ion beams in materials engineering and characterizations 

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    開催期間: 2018年10月09日 - 2018年10月12日   記述言語:英語  

  • Spin-torque ferromagnetic resonance studies in O+ and S+ implanted Pt/Ni80Fe20 thin film

    U. Shashank, R. Medwal, S. Gupta, R. Nongzai, R. S. Rawat, K. Asokan, H. Asada, Y. Fukuma

    5th international conference on ion beams in materials engineering and characterizations 

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    開催期間: 2018年10月09日 - 2018年10月12日   記述言語:英語  

  • Spin-orbit interaction modulation by oxygen ion implantation in Platinum

    T. Shibata

    5th KIT-UPM international symposium on appled engineering and sciences 

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    開催期間: 2017年11月15日   記述言語:英語  

  • Study of YIG for insulator based nanoelectronics devices

    S. Tyagi,

    5th KIT-UPM international symposium on appled engineering and sciences 

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    開催期間: 2017年11月15日   記述言語:英語  

  • Detection of spin current using Spin Hall effect

    A. Deka

    4th KIT-UPM international symposium on appled engineering and sciences 

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    開催期間: 2016年12月18日   記述言語:英語  

  • Basic study of spin wave for new logic device

    R. Kajiwara

    4th KIT-UPM international symposium on appled engineering and sciences 

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    開催期間: 2016年12月18日   記述言語:英語  

  • Detection of voltage excited spin wave by pico-second time-resolved Kerr microscope

    B. Rana

    61st Annual Conference on Magnetism & Magnetic Materials 

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    開催期間: 2016年11月   記述言語:英語  

  • Spin pumping-inverse spin Hall effect: Essential role of magnetization precession cone angle

    S. Gupta

    61st Annual Conference on Magnetism & Magnetic Materials 

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    開催期間: 2016年11月   記述言語:英語  

  • Detection of voltage excited spin wave by ps-TRMOKE

    B. Rana

    International workshop on nano-spin conversion science & quantum spin dynamics(NSCS-QSD), 

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    開催期間: 2016年10月   記述言語:英語  

  • Voltage excited magnetization dynamics: effect of excitation power on spin wave amplitude and damping

    B. Rana

    9th International Conference on Physics and Applications of Spin-Related Phenomena in Solids(PASPS9) 

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    開催期間: 2016年08月   記述言語:英語  

  • Properties of voltage excited magnetization dynamics and spin waves

    B. Rana

    MMM Intermag 2016 Joint Conference 

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    開催期間: 2016年01月   記述言語:英語  

  • Enhancement of voltage modulation of magnetic anisotropy by suppressing angular momentum dissipation

    K. Miura

    MMM Intermag 2016 Joint Conference 

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    開催期間: 2016年01月   記述言語:英語  

  • Excitation of magnetization dynamics in thin CoFeB films by electric field

    B. Rana

    Magnonics 2015 

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    開催期間: 2015年08月   記述言語:英語  

  • Enhancement of variation in direction of magnetization by RF voltage with frequency close to ferromagnetic resonance

    K. Miura

    59th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2014年12月   記述言語:英語  

  • Ferromagnetic-resonance field shift in Py/Cu/Pt tri-layer films

    K. Kondou

    59th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2014年12月   記述言語:英語  

  • Observation of spin to charge conversion by Ag/Bi2O3 interface

    S. Karube

    59th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2014年12月   記述言語:英語  

  • Spin transport properties in LiAl studied by non-local spin injection

    H. Idzuchi

    The 2014 International Magnetics Conference (INTERMAG 2014) 

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    開催期間: 2014年05月   記述言語:英語  

  • Spin wave device using voltage-controlled magnetic anisotropy at MgO/CoFeB interface

    M. Yamada

    58th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2013年12月13日   記述言語:英語  

  • Second harmonic spin waves generation and propagation

    O. Rousseau

    International French-US Workshop -Toward low power spintronic devices 

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    開催期間: 2013年07月13日   記述言語:英語  

  • Hanle velocimetry of diffusive spins in lateral spin valves

    Y. Otani

    The 3rd International Symposium on Advanced Magnetic Materials and Applications(ISAMMA 2013) 

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    開催期間: 2013年07月13日   記述言語:英語  

  • Electric field effect on spin diffusion in Permalloy/MgO/Ag lateral spin valves with HfO2 gate dielectrics

    S. Karube,

    The 8th International Symposium on Metallic Multilayers(MML2013) 

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    開催期間: 2013年05月13日   記述言語:英語  

  • Spin waves and confinement effects

    Z. Lu

    The 8th International Symposium on Metallic Multilayers(MML2013) 

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    開催期間: 2013年05月13日   記述言語:英語  

  • Non-local Hanle effect as a means of velocimetry for diffusive spins in metallic lateral spin valves

    H. Idzuchi

    The 8th International Symposium on Metallic Multilayers(MML2013) 

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    開催期間: 2013年05月13日   記述言語:英語  

  • The development of the non-perturbing electrical detection method of the sole vortex gyration

    S. Sugimoto

    The 8th International Symposium on Metallic Multilayers(MML2013) 

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    開催期間: 2013年05月13日   記述言語:英語  

  • Spin wave modes in cross shaped magnetic nanoelement

    B. K. Mahato

    The 12th Joint MMM/Intermag Conference 

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    開催期間: 2013年01月13日   記述言語:英語  

  • Controlled excitation of the collective dynamics in coupled magnetic vortices

    S. Sugimoto

    The 12th Joint MMM/Intermag Conference 

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    開催期間: 2013年01月13日   記述言語:英語  

  • Effect of spin absorption on presession dynamics of pure spin currents in lateral spin valves

    H. Idzuchi

    The 12th Joint MMM/Intermag Conference 

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    開催期間: 2013年01月13日   記述言語:英語  

  • Influence of lattice symmetry on the magnetization dynamics in artificial ferromagnetic nanodot lattices

    A. Barman

    The 12th Joint MMM/Intermag Conference 

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    開催期間: 2013年01月13日   記述言語:英語  

  • Giant enhancement of spin accumulation and long-distance spin precession in lateral spin valves (invited)

    Y. Fukuma

    Workshop on Innovative Nanoscale Devices and Systems (WINDS) 

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    開催期間: 2012年12月04日   記述言語:英語  

  • Influence of lattice symmetry on the magnonic spectra in magnetic nanodot lattice

    S. Saha,

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • Diffusive transport of pure spin current in lateral spin valves

    Y. Fukuma

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • Enhanced spin accumulation in CoFe/MgO/Ag lateral spin valves

    H. Idzuchi

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • The current induced nonlinear mode splitting of the magnetic vortex

    S. Sugimoto

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • Spin injection into trilayer graphene lateral spin valves

    Y. Liu

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • Transition from collective to non collective regime in the picosecond magnetization dynamics of 50nm permalloy dot arrays

    B. Rana

    International Conference of the Asian Union of Magnetics Societies(ICAUMS) 

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    開催期間: 2012年10月12日   記述言語:英語  

  • Study of the nonlinear effect in current induced core oscillations of a single magnetic vortex

    S. Sugimoto

    The 21th International Colloquium on Magnetic Films and Surfaces(ICMFS) 

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    開催期間: 2012年08月12日   記述言語:英語  

  • Coherence in collective spin precession in lateral spin valves

    H. Idzuchi

    The 19th international conference on magnetism 

     詳細を見る

    開催期間: 2012年07月12日   記述言語:英語  

  • Efficient generation of pure spin current in lateral spin valves

    Y. Fukuma

    WUN-SPIN 2012 

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    開催期間: 2012年07月12日   記述言語:英語  

  • Characterization of epitaxial EuS(111) thin films on BaF2(1111) substrates grown by molecular beam epitaxy

    S. Senba

    The 19th international conference on magnetism 

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    開催期間: 2012年07月12日   記述言語:英語  

  • Detection of picosecond magnetization dynamics of 50nm magnetic dots down to the single nanodot regime

    B. Rana

    The 19th international conference on magnetism 

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    開催期間: 2012年07月12日   記述言語:英語  

  • Optically induced tunable magnetization dynamics in nanoscale Co antidot lattices

    R. Mandal

    The 19th international conference on magnetism 

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    開催期間: 2012年07月12日   記述言語:英語  

  • Coherency in collective spin precession in lateral spin valves(invited)

    Y. Otani

    INTERMAG 2012 

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    開催期間: 2012年05月12日   記述言語:英語  

  • Giant spin accumulation and long-distance spin precession in metallic lateral spin valves

    Y. Fukuma

    APS March Meeting 2012 

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    開催期間: 2012年02月   記述言語:英語  

  • Enhanced spin accumulation in multiterminal lateral spin valves

    H. Idzuchi

    56th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2011年11月02日 - 2011年11月03日   記述言語:英語  

  • Long-distance spin precession in non-local lateral spin valves with giant spin accumulation(Invited)

    Y. Otani

    56th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2011年11月02日 - 2011年11月03日   記述言語:英語  

  • Transport properties of GeMnTe/GeTe/EuS/GeTe quasimagnetic tunnel junctions grown by molecilar beam epitaxy

    H. Asada

    56th Annual Conference on Magnetism and Magnetic Materials 

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    開催期間: 2011年11月02日 - 2011年11月03日   記述言語:英語  

  • Anisotropy and damping in collective precessional dynamics in arrays of Ni80Fe20 nanoelements

    B. Rana

    56th Annual Conference on Magnetism and Magnetic Materials 

     詳細を見る

    開催期間: 2011年10月31日   記述言語:英語  

  • Temperature dependence of magnetoresistance in Permalloy-contacted silicon nanowire spin valves

    J.L. Tarun

    International workshop on quantum nanostructures and nanoelectronics (QNN 2011) 

     詳細を見る

    開催期間: 2011年10月03日   記述言語:英語  

  • Coupled vortex dynamics in Permalloy submicron disk pairs (invited)

    Y. Otani

    5th International Workshop on Amorphous and Nanostructured Magnetic Materials(ANMM'2011) 

     詳細を見る

    開催期間: 2011年09月   記述言語:英語  

  • Magnetoresistance in silicon nanowire with two-terminal cobalt electrodes

    J.L. Tarun

    2011シリコンナノエレクトロニクスワークショップ 

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    開催期間: 2011年06月12日 - 2011年06月13日   記述言語:英語  

  • Transition from a collective to non-collective precessional dynamics in nanomagnet arrays

    B. Rana

    IEEE International Magnetics conference  

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    開催期間: 2011年04月11日   記述言語:英語  

  • Strongly enhanced spin accumulation by introducing MgO interface layer in non-local spin valves (invited)

    Y. Fukuma

    IEEE International Magnetics conference  

     詳細を見る

    開催期間: 2011年04月11日   記述言語:英語  

  • Spin-flip mechanism in Ag nanowire

    H. Idzuchi

    IEEE International Magnetics conference  

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    開催期間: 2011年04月11日   記述言語:英語  

  • Dynamics of coupled magnetic vortices via magnetic dipolar interaction

    S. Sugimoto

    IEEE International Magnetics conference  

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    開催期間: 2011年04月11日   記述言語:英語  

  • Coupled vortex dynamics in Permalloy submicron disk pairs

    S. Sugimoto

    International Conference of AUMS(ICAUMS2010) 

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    開催期間: 2010年12月   記述言語:英語  

  • Efficient spin accumulation by introducing MgO interface

    Y. Otani

    APLフォーラム2010、スピントロニクスの今後の方向性 

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    開催期間: 2010年11月   記述言語:英語  

  • Efficient spin injection through low resistive MgO layer in Permalloy/Ag lateral spin valves

    Y. Fukuma

    第55 回 磁性と磁性材料学会 

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    開催期間: 2010年11月   記述言語:英語  

  • Spin valve effects in silicon nanowires

    J.L. Tarun

    第55 回 磁性と磁性材料学会 

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    開催期間: 2010年11月   記述言語:英語  

  • Current excitation of translational modes in magnetostatically coupled magnetic vortices

    S. Sugimoto

    第7回金属多層膜IEEE国際シンポジウム(MML2010) 

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    開催期間: 2010年09月19日 - 2010年09月24日   記述言語:英語  

  • Spin transport in lateral spin valves consisting of permalloy and nonmagnetic Cu, Ag, or Mg with MgO interface layer

    Y. Otani

    第7回金属多層膜IEEE 国際シンポジウム(MML2010) 

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    開催期間: 2010年09月19日 - 2010年09月24日   記述言語:英語  

  • Spin injection into magnesium nanowire

    H. Idzuchi

    第7 回金属多層膜IEEE 国際シンポジウム(MML2010) 

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    開催期間: 2010年09月19日 - 2010年09月24日   記述言語:英語  

  • GeTe based ferromagnetic semiconductor layers

    Y. Fukuma

    E-MRS 2010秋季大会 

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    開催期間: 2010年09月13日 - 2010年09月17日   記述言語:英語  

  • Gyrotropic mode splitting in pair of magnetostatically coupled Permalloy disks in an ordered array

    A. Barman

    電磁気学研究シンポジウム2010年 

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    開催期間: 2010年07月05日 - 2010年07月08日   記述言語:英語  

  • Simulation studies of propagation of local magnetic excitation in one dimensional chains of nanomagnets

    S. Barman

    電磁気学研究シンポジウム2010年 

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    開催期間: 2010年07月05日 - 2010年07月08日   記述言語:英語  

  • Spin injection and absorption efficiency in metallic and superconductive lateral spin valves

    Y. Otani

    国際物質·材料研究先端材料学会 

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    開催期間: 2010年05月30日 - 2010年06月04日   記述言語:英語  

  • Pure-spin-current induced switching and interface contribution

    Y. Otani

    第11 回磁性・磁性材料国際磁気学会  

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    開催期間: 2010年01月18日 - 2010年01月22日   記述言語:英語  

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講演

  • Classification tasks using nonlinear magnetization dynamics

    Brain inspired computing -physics, architectures, materials, applications- NTU-JSPS joint seminar   2021年12月 

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    発表言語:英語   講演種別:招待講演  

  • Spin to charge conversion for terahertz spintronics

    47th IEEE International conference on Plasma Sciences and 2nd Asia-Pacific conference on Plasma and Terahertz Science  2020年12月 

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    開催期間: 2020年12月06日 - 2020年12月10日   発表言語:英語   講演種別:招待講演  

  • Spin to charge conversion for terahertz spintronics

    47th IEEE International conference on Plasma Sciences and 2nd Asia-Pacific conference on Plasma and Terahertz Science  2020年12月 

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    発表言語:英語   講演種別:招待講演  

  • Toward voltage driven spintronic devices

    20th International worshop on the physics of semiconductor devices  2019年12月 

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    発表言語:英語   講演種別:招待講演  

  • Toward voltage driven spintronic devices

    20th International worshop on the physics of semiconductor devices  2019年12月 

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    開催期間: 2019年12月17日 - 2019年12月20日   発表言語:英語   講演種別:招待講演  

  • Spin pumping, spin Hall effect and spin seebeck effect

    63rd DAE solid state physics state symposium  2018年12月 

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    発表言語:英語   講演種別:招待講演  

  • Spin pumping, spin Hall effect and spin seebeck effect

    63rd DAE solid state physics state symposium  2018年12月 

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    開催期間: 2018年12月18日 - 2018年12月22日   発表言語:英語   講演種別:招待講演  

  • Spin current generation by spin pumping

    International conference on magnetic materials and applications  2018年12月 

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    発表言語:英語   講演種別:招待講演  

  • Spin current generation by spin pumping

    International conference on magnetic materials and applications  2018年12月 

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    開催期間: 2018年12月09日 - 2018年12月13日   発表言語:英語   講演種別:招待講演  

  • Magnetization dynamics and its application

    International conference on current trends in materials science and engineering  2018年01月 

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    開催期間: 2018年01月19日 - 2018年01月20日   発表言語:英語   講演種別:招待講演  

  • Magnetization dynamics and its application

    International conference on current trends in materials science and engineering  2018年01月 

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    発表言語:英語   講演種別:招待講演  

  • Spin transport and high frequency magnetization dynamic analysis in magnetic thin films

    5th KIT-UPM international symposium on appled engineering and sciences  2017年11月 

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    開催期間: 2017年11月15日   発表言語:英語   講演種別:特別講演  

  • Spin-Charge interconversion at interfaces and surfaces with spin splitting

    International Workshop and School on Spin Transfer  2016年09月 

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    開催期間: 2016年09月   発表言語:英語   講演種別:特別講演  

  • Fermi level dependent charge-to-spin current conversion by Dirac surface state of topological insulators

    9th International Conference on Physics and Applications of Spin-Related Phenomena in Solids(PASPS9)  2016年08月 

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    開催期間: 2016年08月   発表言語:英語   講演種別:特別講演  

  • Spin injection and transport properties in lateral spin valves

    Indo-Japan Workshop on Magnetism at Nanoscale (IJWMN)  2015年01月 

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    開催期間: 2015年01月10日   発表言語:英語   講演種別:特別講演  

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担当授業科目(学内)

  • 2023年度   マイクロ・ナノシステム技術特論BP

  • 2023年度   マイクロ・ナノシステム技術特論EP

  • 2023年度   磁気記録工学特論

  • 2023年度   電気システム回路Ⅱ

  • 2023年度   電気システム回路Ⅰ

  • 2022年度   マイクロ・ナノシステム技術特論EP

  • 2022年度   磁気記録工学特論

  • 2022年度   電気システム回路Ⅱ

  • 2022年度   電気システム回路Ⅰ

  • 2021年度   磁気記録工学特論

  • 2021年度   電気システム回路Ⅱ

  • 2021年度   電気システム回路Ⅰ

  • 2021年度   情報工学基礎実験

  • 2020年度   磁気記録工学特論

  • 2020年度   電気システム回路Ⅱ

  • 2020年度   電気システム回路Ⅰ

  • 2020年度   情報工学基礎実験

  • 2019年度   磁気記録工学特論

  • 2019年度   電気システム回路Ⅱ

  • 2019年度   電気システム回路Ⅰ

  • 2019年度   情報工学基礎実験

  • 2019年度   電子マテリアル工学

  • 2018年度   情報工学基礎実験

  • 2018年度   磁気記録工学特論

  • 2018年度   電子マテリアル工学

  • 2017年度   磁気記録工学特論

  • 2017年度   電子情報セミナー I

  • 2017年度   電子マテリアル工学

  • 2016年度   磁気記録工学特論

  • 2016年度   電子マテリアル工学

  • 2015年度   磁気記録工学特論

  • 2015年度   電子マテリアル工学

  • 2014年度   磁気記録工学特論

  • 2014年度   電子マテリアル工学

▼全件表示

国際交流窓口担当

  • アミティ大学 アミティナノテクノロジー研究院  インド  2019年09月 - 現在

  • デリー大学  インド  2018年08月 - 現在

  • 南洋理工大学 国立教育研究院  シンガポール共和国  2017年11月 - 現在

その他国際交流活動

  • さくらサイエンス(デリ大学、アミティ大学)

    活動期間: 2022年01月

  • さくらサイエンス(アミティ大学、デリ大学)

    活動期間: 2020年01月

  • さくらサイエンス(デリ大学、ラジシャヒ大学、南洋理工大学)

    活動期間: 2019年11月

  • さくらサイエンス(デリ大学、南洋理工大学、大学間利用加速器研究センター)

    活動期間: 2019年01月

  • さくらサイエンス(インド工科大学デリ校)

    活動期間: 2018年10月 - 2018年11月

  • さくらサイエンス(南洋理工大学、大学間利用加速器研究センター)

    活動期間: 2017年12月

▼全件表示