2024/05/14 更新

写真a

ホ ジョンフン
許 宗焄
HUH Jong-Hoon
Scopus 論文情報  
総論文数: 0  総Citation: 0  h-index: 6

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
外部リンク

研究キーワード

  • 非平衡物理

研究分野

  • ナノテク・材料 / 応用物理一般

  • 情報通信 / 計算科学

  • 自然科学一般 / 数理物理、物性基礎

出身学校

  • 1986年03月   釜山大学校   理学部   物理学   卒業   大韓民国

出身大学院

  • 2000年03月   九州大学   工学研究科   応用物理学   博士課程・博士後期課程   修了   日本国

取得学位

  • 九州大学  -  博士(工学)   2000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

  • 2013年10月 - 2019年03月   九州工業大学   大学院情報工学研究院   機械情報工学研究系     教授

所属学会・委員会

  • 2000年04月 - 現在   日本物理学会   日本国

  • 2000年04月 - 現在   日本液晶学会   日本国

論文

  • Colored noise-induced threshold shifts and phase diagrams in electroconvections 査読有り 国際誌

    JONG-HOON HUH, SHOICHI KAI

    Journal of the Physical Society of Japan   83 ( 6 )   063601-1 - 063601-4   2014年06月

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

    DOI: 10.7566/JPSJ.83.063601

    Kyutacar

    Scopus

    CiNii Article

  • Control of stochastic and inverse stochastic resonances in a liquid-crystal electroconvection system using amplitude and phase noises 査読有り

    Huh J.H., Shiomi M., Miyagawa N.

    Scientific Reports   13 ( 1 )   2023年12月

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

    Stochastic and inverse stochastic resonances are counterintuitive phenomena, where noise plays a pivotal role in the dynamics of various biological and engineering systems. Even though these resonances have been identified in various systems, a transition between them has never been observed before. The present study demonstrates the presence of both resonances in a liquid crystal electroconvection system using combined amplitude and phase noises, which correspond to colored noises with appropriate cutoff frequencies (i.e., finite correlation times). We established the emergence of both resonances and their transition through systematic control of the electroconvection threshold voltage using these two noise sources. Our numerical simulations were experimentally confirmed and revealed how the output performance of the system could be controlled by combining the intensity and cutoff frequency of the two noises. Furthermore, we suggested the crucial contribution of a usually overlooked additional phase noise to the advancements in various noise-related fields.

    DOI: 10.1038/s41598-023-44043-4

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85173644661&origin=inward

  • Nonequilibrium phase transitions of a nematic liquid crystal under ac field-driven electroconvection 査読有り 国際誌

    Huh J.H.

    Physical Review E   106 ( 1 )   2022年07月

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    担当区分:筆頭著者, 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 report on phase transitions between isotropic and nematic liquid crystal phases in nonequilibrium systems (NESs). ac field-driven electroconvection (EC) provides an NES, which can be well controlled by the voltage V and frequency f; it arises electrohydrodynamically at a threshold voltage Vc. In continuous cooling and heating processes with various rates R, the critical temperature Tc was determined at a critical time tc for phase transitions. Moreover, the morphological and dynamical features in the phase transitions were examined using an electro-optical image processing method. In comparison with an equilibrium system (V=0), two typical turbulent ECs (i.e., NESs), which are called dynamic scattering mode 1 (DSM1 for V>Vc) and DSM2 (for V≫Vc), were examined to understand the nonequilibrium phase transitions. In particular, our results show that in high voltage-induced turbulence (i.e., DSM2), Tc can be determined effectively without considering R; this provides a possibility for a material technology application in nonequilibrium-based circumstances.

    DOI: 10.1103/PhysRevE.106.014702

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85134887584&origin=inward

  • Reentrant prewavy instability in competition between rising and twist modes in ac field-driven electroconvection 査読有り 国際誌

    Huh J.H., Miyagawa N.

    Physical Review E   103 ( 6 )   062701-1 - 062701-11   2021年06月

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

    We report on the prewavy (PW) instability in ac field-driven electrohydrodynamics that is induced in a nematic liquid crystal (NLC) sandwiched between parallel electrodes. The instability is characterized by a twist mode of the NLC director along the vertical orientation to the electrodes (i.e., the z axis), generating a periodic pattern having a large wavelength (λPW) in the xy plane. The PW periodic to the preferred director n0 of the NLC should be distinguished from well-known electroconvection (EC) such as normal rolls (NRs) and abnormal rolls (ARs) with similar wave vectors. A reentrant PW (PW2) was discovered by employing well-adjusted optical conditions and a dynamic image-process method. The wavelength λPW2 of the PW2 accompanying turbulent EC was measured as functions of the applied ac voltage and frequency, which was distinguished from λPW1 of the primary PW (PW1) separated from the NR. Moreover, the appearance, disappearance, and reappearance of the PW were investigated for five frequency regions classified in the ac field-driven EC; it was found that the high frequency and high voltage causes competition between the rising mode (θ, tilting angle to the xy plane) and twist mode (φ, in-plane angle to the x axis) of the director through electrohydrodynamic coupling between the director field and flows. We discuss how the PW2 can arise by considering another twist mode known as AR instability.

    DOI: 10.1103/PhysRevE.103.062701

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85108073582&origin=inward

  • Prewavy instability-originated dielectric chevrons of electroconvection in nematic liquid crystals 査読有り 国際誌

    Shiomi M., Choi E.J., Huh J.H.

    Physical Review E   102 ( 4 )   042704-1 - 042704-8   2020年10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)

    © 2020 American Physical Society. This paper reports the pattern formation and evolution in a high-frequency dielectric regime observed in the AC-driven electroconvection of nematic liquid crystals (NLCs). It is determined that prewavy (PW) instability is essential for the formation and evolution. Specifically, in a twisted-aligned NLC cell, we observe a unique pattern that is comparable to the dielectric chevrons (DCVs) typically observed in a conventional planarly aligned pattern. It is determined to be a combined PW pattern with dielectric normal rolls (DNRs). Moreover, the power indices (αPW, αDNR, and αDCV) are determined from the frequency-dependent thresholds (Vth∝fα) of PW, DNR, and DCV. By taking into account the appearance of PW and the different power indices, the pattern evolution scenarios for DCV are proposed, which can well explain the previous experimental results. Specifically, the PW-originated DCV2 clearly differs from the defect-mediated DCV1, which is known as a typical pattern evolution.

    DOI: 10.1103/PhysRevE.102.042704

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85094821952&origin=inward

  • Phase Transition Temperatures of a Nematic Liquid Crystal in the Presence of Noise and DC Fields 査読有り 国際誌

    Huh J.H., Higashi T., Yamasaki T., Nagaya T.

    Journal of the Physical Society of Japan   93 ( 4 )   2024年04月

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

    Thermal phase transitions from a nematic liquid-crystal phase to an isotropic phase are reported in this study. The phase transition temperature Tc under noise and DC fields was examined during continuous heating processes with different heating rates R (1–10 °C=min). Tc was determined as functions of the noise intensity VN and the DC intensity V. Evidently, Tc shows different behavior with respect to the fields at fixed values of R. Tc decreased monotonously with VN, whereas it exhibited nonmonotonic behavior in Tc(V). These shifts in Tc are quite different from that previously observed in the AC field. It was found that DC field-induced electroconvection is responsible for the unexpected nonmonotonic behavior. In particular, the transition between the dynamic scattering modes (i.e., DSM1 and DSM2) may be related to this behavior. The different behavior for the noise and DC fields was confirmed using various values of R. Furthermore, the present results in comparison with the previous results for the AC field were discussed.

    DOI: 10.7566/JPSJ.93.044601

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85189322354&origin=inward

  • A Study on Occlusion Removal Technology Using Integral Imaging with Semantic Segmentation and Predictive Labeling 査読有り

    Kim H.W., Huh J.H., Lee M.C.

    International Conference on Control, Automation and Systems   1694 - 1699   2023年01月

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    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 paper, we propose an improved occluded object visualization method using semantic segmentation and predictive labeling based on integral imaging (InIm) technology. InIm is a passive 3D visualization technique that can generate 3D information through elemental images with different perspectives of information about an object and, it can be used to remove occlusion. However, occlusion pixels in elemental images can degrade the quality of reconstructed images. Our proposed method can remove occlusion and visualize the object of interest. In addition, we propose a predictive labeling method for reducing processing time, which can generate accurate 3D object information without occlusion. Therefore, when the proposed method is commercialized, it is expected to contribute to increasing the safety of autonomous driving technology.

    DOI: 10.23919/ICCAS59377.2023.10316784

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85179176903&origin=inward

  • Optimal focal plane analysis research using noise caused by depth of field of objective lens in digital holographic microscopy (DHM) 査読有り 国際誌

    Kim, Hyun-Woo, Cho, Myungjin, Huh, Jong-Hoon, Lee, Min-Chul

    37th International Technical Conference on Circuits/Systems, Computers and Communications, ITC-CSCC 2022 ( Institute of Electrical and Electronics Engineers Inc. )   368 - 371   2022年11月

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    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)

    Thailand   Phuket   2022年07月05日  -  2022年07月08日

    In digital holographic microscopy (DHM) technol-ogy, we have to record a magnified laser beam that has passed through an objective lens onto an image sensor. In this process, when the specimen is not positioned on the accurate focal plane of the objective lens, a noise called a phase error occurs. This phase error becomes a factor that prevents accurate analysis by the observer. In addition, as the magnification of the objective lens increases, the depth of field becomes narrow, making it difficult to find an accurate focal plane. To solve this problem, we propose a method to find the optimal focal plane using the noise map generated by the recorded holographic video. In this paper, we verify the effectiveness of the proposed method by comparing the optimal 3D profile in the focal plane found by the proposed method and the 3D profile in a different position with the ideal comparison target, respectively.

    DOI: 10.1109/ITC-CSCC55581.2022.9895093

    DOI: 10.1109/ITC-CSCC55581.2022.9895093

    Scopus

    その他リンク: https://ieeexplore.ieee.org/document/9895093

  • Photon counting integral imaging using Kalman estimation 査読有り 国際誌

    Shinohara R., Kim H.W., Lee J., Huh J.H., Cho M., Lee M.C.

    International Conference on ICT Convergence   2022-October   244 - 249   2022年10月

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    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 paper, we propose 3D photon counting integral imaging using the Kalman estimation. Photons are emitted in unit time and space independently. To visualize the 3D object under low luminance conditions, computational photon counting imaging may be used. It can estimate the photons by statistical methods such as the Poisson random distribution. Then, it can reconstruct the 3D information through the integral imaging. However, since the Poisson random process always generates different photon counting images, the image quality is not consistent and also errors may occur. Therefore, it is difficult to maintain the high 3D image quality under photon-starved conditions. To solve these problems, we utilize Kalman estimation to estimate the photons accurately and generate the high image quality consistently under various low light conditions. To evaluate our proposed method, we implemented optical experiments and image quality evaluation by calculating image quality metrics.

    DOI: 10.1109/ICTC55196.2022.9952470

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85143254654&origin=inward

  • Voltage Dependence of Phase Transition Temperatures of a Nematic Liquid Crystal under AC Field-Driven Electroconvection 査読有り 国際誌

    Huh J.H., Nagaya T.

    Journal of the Physical Society of Japan   91 ( 9 )   2022年09月

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    担当区分:筆頭著者, 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 report on phase transitions between isotropic and nematic liquid crystal phases in the presence of AC voltages, which provide various director fields. Above a critical voltage Vc, some complicated director fields can be realized by electroconvection (EC). In continuous cooling and heating processes at a fixed rate (R = 10 °C=min), the critical temperature Tc was determined for the phase transitions using an optical image processing method. In addition, the Vdependence of characteristic optical intensities, such as minimal and maximal peaks, were examined. The shift of Tc, ΔTc = |Tc(V ) - Tc(0)|, is found in comparison with ΔTc ∞ V2 predicted in the case of no EC (V < Vc). A serious deviation from the prediction originates from the V-dependent director fields and flows of various types of EC, such as soft-mode turbulence and dynamic scattering modes (DSM1 and DSM2). In the relationship, ΔTc ∞ Vα, it is found that α ∼ 2 for V < Vc, α ∼ 0 for Vc < V < VDSM1, α ∼ 0.8 for VDSM1 < V < VDSM2, and α ∼ 2 for VDSM2 < V. Our results show a possibility for a material technology application in nonequilibrium circumstances.

    DOI: 10.7566/JPSJ.91.094604

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85148534870&origin=inward

  • Control of the Orientation of Traveling Waves in AC-Driven Electroconvection by Additional Fields 査読有り 国際誌

    Horikawa Akira, Huh Jong-Hoon

    Journal of the Physical Society of Japan ( Journal of the Physical Society of Japan )   89 ( 3 )   034602-1 - 034602-3   2020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)

    In the presence of a superimposing noise or an additional magnetic field, AC-driven traveling waves (TWs) in a nematic liquid crystal (NLC) are investigated. The orientation of the right-going TW (RTW) and left-going TW (LTW) is changed by disclinations of the NLC or the magnetic field-induced distortion of the director; in particular, the transition between the RTW and LTW is successfully controlled by the magnetic field.

    DOI: 10.7566/JPSJ.89.034602

    Scopus

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/210000158059

  • Additional Deterministic and Stochastic Field-Induced Shifts of the Threshold and Wavenumber of AC-Driven Electroconvection in Nematic Liquid Crystals 査読有り 国際誌

    Miyagawa Naoto, Yano Yoshimitsu, Huh Jong-Hoon

    Journal of the Physical Society of Japan ( Physical Society of Japan )   89 ( 9 )   095003-1 - 095003-2   2020年09月

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    担当区分:筆頭著者, 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 report shifts of the threshold and wavenumber of ac-driven electroconvection (EC) in nematic liquid crystals under additionally applied deterministic and stochastic amplitudes and phases. A robust relationship (VT=k2c =const:) between the total effective voltage VT and wavenumber kc (at the onset of EC) was found, despite various shifts depending on the additional parameters.

    DOI: 10.7566/JPSJ.89.095003

    Scopus

    CiNii Article

    CiNii Research

    その他リンク: https://ci.nii.ac.jp/naid/210000158478

  • Characterization of surface anchoring energy of nematic liquid crystals via electrohydrodynamic instability 査読有り 国際誌

    Ryu D.G., Huh J.H., Kim Y.K., Gwag J.S.

    Physical Review E   101 ( 6 )   062703-1 - 062703-7   2020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)

    © 2020 American Physical Society. Herein, a method is proposed to determine the azimuthal anchoring energies of surface liquid crystals (LCs), as they gradually change orientation from a vertical to a horizontal state owing to an increase in the voltage applied to each LC cell. The LC cells are characterized using the direction of the Williams roll pattern related to the midplane LC director of the conduction regime of the electrohydrodynamic convection patterns of LCs. The application of the midplane LC directions, obtained from the direction of the roll patterns, to the Ericksen-Leslie equation produces the precise values of the surface anchoring strength. The hybrid type 90°-twisted nematic LC cell, composed of homeotropic and homogeneous LC alignment layers on the top and bottom substrates, respectively, was used to find the azimuthal anchoring energy of the surface LCs, indicated by voltages at the initially vertically aligned LC state. It was observed that the surface azimuthal anchoring energy on the homeotropic layer increased with an increase in voltage. We expect that the proposed technique may be excellent in terms of ease of use, simplicity, and accuracy because the azimuthal anchoring energy can be visually evaluated through the roll pattern.

    DOI: 10.1103/PhysRevE.101.062703

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85087156304&origin=inward

  • Formation of grid patterns in an ac-driven electroconvection system 査読有り 国際誌

    Jong-Hoon Huh, Haruki Osoguchi

    Physical Review E   101 ( 6 )   062701-1 - 062701-9   2020年06月

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

    We report the formation mechanism of a unique pattern observed in ac-driven electroconvection of nematic liquid crystals (NLCs), in which many well-organized grid cells are very regularly aggregated in a two-dimensional plane, globally forming a nearly perfect grid pattern (GP). Intuitively, the formation of such a pattern is unpredictable; usually, the perfectly regular normal roll (NR) showing a preferred roll direction is observed in this system by imposing a fixed initial direction of an NLC. The GP was investigated by varying the ac voltage and frequency. To characterize the GP, the density ρGP, the width a and length b of the grids, and the oscillation period TGP of an inner optical pattern of the grids were measured; moreover, the lengths Lx and Ly characterizing phase-jump lines (PJLs) in the GP were examined. By taking into account the process of evolution from a fluctuating NR with defects to the GP, the velocity and director fields of the GP are estimated. Furthermore, in comparison with the bimodal mechanism proposed in the earlier study, a possible mechanism for the GP formed by the PJLs is discussed; various routes to GPs depending on the ac frequency are proposed.

    DOI: 10.1103/PhysRevE.101.062701

    Scopus

    その他リンク: https://journals.aps.org/pre/abstract/10.1103/PhysRevE.101.062701

  • ポペット弁の内部流れ解析

    廣瀬直紀, 清水文雄, 許 宗焄

    フルードパワーシステム講演会講演論文集 ( 日本フルードパワーシステム学会 )   2020 ( 0 )   47 - 49   2020年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/40022444137/

  • 液晶電気対流系における外乱の効果

    宮川 直人, 矢野芳光,許 宗焄

    日本液晶学会討論会講演予稿集 ( 一般社団法人 日本液晶学会 )   2020 ( 0 )   PB01 - PB01   2020年01月

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    担当区分:責任著者   記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    We investigated effects of controlled stimuli on ac-driven electroconvection (EC) in nematic liquid crystals. We examined shifts of the threshold voltage and wavenumber of EC under additionally applied various stimuli. A robust and universal relationship between the total effective voltage and wavenumber (at the onset of EC) was found, despite various shifts depending on the additional parameters; it was independent of the type or presence of stimuli. In this relationship, the critical wavenumber is consistently determined by the total effective voltage. The results of this study may help to control nonequilibrium dissipative systems in various external stimuli.

    DOI: 10.11538/ekitou.2020.0_PB01

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/130008047325

  • 誘電領域における電気流体的不安定性の調査

    塩見 雅人, 宮川 直人, 許 宗焄

    日本液晶学会討論会講演予稿集 ( 一般社団法人 日本液晶学会 )   2020 ( 0 )   PA01 - PA01   2020年01月

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    担当区分:最終著者, 責任著者   記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    In this study, we investigated formation scenarios of Chevrons (CV) in the high-frequency dielectric regime of ac-driven electroconvection in nematic liquid crystals (NLC). The frequency dependence of the threshold voltage of CV was examined using several cells controlled by the mixing ratio of two typical NLC (MBBA and EBBA). It is found that three CV formation scenarios are possible by the change in the threshold voltage of Prewavy instability. We discuss them in comparison with conventional CV formation mechanisms.

    DOI: 10.11538/ekitou.2020.0_PA01

    CiNii Article

    CiNii Research

    その他リンク: https://ci.nii.ac.jp/naid/130008047312

  • 膜厚比の異なるバイモルフ構造の導電性高分子ソフトアクチュエータ

    林 瑞樹, 許 宗焄, 渕脇 正樹

    年次大会 ( 一般社団法人 日本機械学会 )   2020 ( 0 )   J11119   2020年01月

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    記述言語:日本語   掲載種別:研究論文(研究会,シンポジウム資料等)

    Soft actuators, or artificial muscles, based on conducting polymers, constitute the base for the development of promising polymeric sensing motors, tools for surgeons, or zoomorphic and anthropomorphic soft robots. Some electrochemical characterizations of these soft actuators of artificial muscles have been already reported. In this study, the behaviors of the asymmetric bilayer artificial muscles, PPy-ClO<sub>4</sub>/PPy-DBS worked in 0.5 M NaClO<sub>4</sub> aqueous solutions were discussed by the dynamo-voltammetric responses and coulo-dynamic Evolution responses. Especially, the authors are focusing on the thickness ratio between the PPy-ClO<sub>4</sub> and the PPy-DBS layers in this study. In this study, the author investigates the dynamic behavior of the bending actuation of the asymmetric bilayer artificial muscles based on some kinds of the thickness ratio between the anion-driven and the cation-driven layers.

    DOI: 10.1299/jsmemecj.2020.J11119

    CiNii Article

    CiNii Research

    その他リンク: https://ci.nii.ac.jp/naid/130008003843

  • Phase noise can induce stochastic resonance? 査読有り 国際誌

    Huh J. -H., Yano Y., Miyagawa N.

    Journal of the Physical Society of Japan   88 ( 6 )   2019年06月

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    担当区分:筆頭著者, 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)

    © 2019 The Physical Society of Japan We investigated stochastic resonance (SR) of ac-driven electroconvection (EC) in nematic liquid crystals by employing the phase noise of the ac field. The phase noise smoothly varies the threshold of EC, as the amplitude noise does it. Surprisingly, a kind of phase stochastic resonance (PSR) is discovered in appropriately colored phase noises; thus, it provides nonmonotonic behavior of the threshold in which a peak of the pattern amplitude of EC is found as a function of the phase noise intensity. The colored and white phase noises are discussed for understanding the PSR.

    DOI: 10.7566/JPSJ.88.063001

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=85067277901&origin=inward

  • Traveling Waves in One-Dimensional Electroconvection of Nematic Liquid Crystals 査読有り

    Horikawa Akira, Huh Jong-Hoon

    Journal of the Physical Society of Japan ( 日本物理学会 )   88 ( 3 )   34602 - 1-6   2019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)

    We report ac-driven electroconvection (EC) of nematic liquid crystals (NLCs) in one-dimensional cells employing an in-plane switching mode. The dynamical features of traveling waves (TWs), such as their velocity and the change in their propagating direction, are examined by varying the ac voltage V and frequency f. In particular, two-mode TWs are discovered; one showing a larger amplitude and a lower velocity arises, evolves, and vanishes randomly in time and space, while the other showing a smaller amplitude and a higher velocity moves continuously; the former appears to be a secondary wave that originates from an unknown instability. Moreover, the change in TW directions is found through turbulence causing disclinations of the director field of NLCs. Evidently, the disclinations play a role as a source or a sink of TWs.

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/120006796382

  • Traveling waves in one-dimensional electroconvection of nematic liquid crystals 査読有り 国際誌

    Horikawa A., Huh J.

    Journal of the Physical Society of Japan   88 ( 3 )   2019年01月

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    担当区分:筆頭著者, 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 report ac-driven electroconvection (EC) of nematic liquid crystals (NLCs) in one-dimensional cells employing an in-plane switching mode. The dynamical features of traveling waves (TWs), such as their velocity and the change in their propagating direction, are examined by varying the ac voltage V and frequency f. In particular, two-mode TWs are discovered; one showing a larger amplitude and a lower velocity arises, evolves, and vanishes randomly in time and space, while the other showing a smaller amplitude and a higher velocity moves continuously; the former appears to be a secondary wave that originates from an unknown instability. Moreover, the change in TW directions is found through turbulence causing disclinations of the director field of NLCs. Evidently, the disclinations play a role as a source or a sink of TWs.

    DOI: 10.7566/JPSJ.88.034602

    Scopus

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  • State transition at electrohydrodynamic convection of twisted nematic liquid crystals 査読有り 国際誌

    Chul Gyu Jhun, Gyu Jin Choi, Dae Geon Ryu, Jong-Hoon Huh, Jin Seog Gwag

    Physical Review E   58 ( 5 )   2018年11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)

    © 2018 American Physical Society. We study electrohydrodynamic convection (EHC) patterns in twisted nematic liquid crystal (TNCL) cells with an initial homeotropic alignment. In addition, we demonstrate switching characteristics due to the transition between the 90° and −90∘ twisted states. The pattern formations are similar to those obtained in a parallel-aligned nontwisted liquid crystal cell. Calculations of the free energy in an initially, homeotropically aligned TNLC in an electric field demonstrate that the energy barrier between the two states decreases with the increase of the electric field. The mutual transition is caused by the fluctuating flow at the dynamic scattering mode 2, where the energy barrier between the two states is reduced by applying a strong electric field. These properties may be employed for the development of a redirectable dynamic lenticular lens, as an extended version of the dynamic lenticular lens using EHC. The transition between the two states caused by EHC is reversible, and the convection roll pattern of the Williams domain rotates by 90° at each transition.

    DOI: 10.1103/PhysRevE.98.052704

    Scopus

    その他リンク: https://journals.aps.org/pre/abstract/10.1103/PhysRevE.98.052704

  • Electroconvection in one-dimensional liquid crystal cells 査読有り 国際誌

    Huh J.

    Physical Review E   97 ( 4 )   2018年04月

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    担当区分:筆頭著者, 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)

    © 2018 American Physical Society. We investigate the alternating current (ac) -driven electroconvection (EC) in one-dimensional cells (1DCs) under the in-plane switching mode. In 1DCs, defect-free EC can be realized. In the presence and absence of external multiplicative noise, the features of traveling waves (TWs), such as their Hopf frequency fH and velocity, are examined in comparison with those of conventional two-dimensional cells (2DCs) accompanying defects of EC rolls. In particular, we show that the defects significantly contribute to the features of the TWs. Additionally, owing to the defect-free EC in the 1DCs, the effects of the ac and noise fields on the TW are clarified. The ac field linearly increases fH, independent of the ac frequency f. The noise increases fH monotonically, but fH does not vary below a characteristic noise intensity VN∗. In addition, soliton-like waves and unfamiliar oscillation of EC vortices in 1DCs are observed, in contrast to the localized EC (called worms) and the oscillation of EC rolls in 2DCs.

    DOI: 10.1103/PhysRevE.97.042707

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  • Visual evaluation of surface anchoring strength by electrohydrodynamic convection of a nematic liquid crystal 査読有り 国際誌

    Choi G., Song J., Jhun C., Huh J., Gwag J.

    Physical Review E   96 ( 4 )   2017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)

    © 2017 American Physical Society. Visual evaluation of the surface anchoring energies in a nematic liquid crystal (LC) cell is characterized by the direction of the convection roll pattern that appears in the low-frequency conduction regime. The convection roll pattern in a twisted nematic LC (TNLC) cell is oriented perpendicular to the midplane LC director dominating the direction of convection flow, and its direction is determined by the relative surface anchoring energy between two surface boundaries. Thus the direction of the roll pattern generated at the TNLC cell with asymmetric LC alignment layers can provide information on the surface anchoring energies at the two boundaries. We demonstrate a method for determining the two anchoring energies through a measured midplane LC director applied to the Ericksen-Leslie equation.

    DOI: 10.1103/PhysRevE.96.040701

    Scopus

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  • Noise-induced traveling waves in electroconvection 査読有り 国際誌

    Huh J.

    2017 International Conference on Noise and Fluctuations, ICNF 2017   2017年07月

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    担当区分:筆頭著者, 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)

    © 2017 IEEE. We report on ac-driven electroconvection (EC) in a nematic liquid crystal (NLC) under superposed multiplicative noise; the EC system consists of a thin layer (d = 10-100 μm) of an NLC in an applied electric field. Ac-driven traveling waves (TWs) have been one of attractive EC showing a Hopf bifurcation, which have been well explained by a weak-electrolyte model. In this paper, noise-induced traveling waves (TWs) are presented in comparison with ac-driven TWs. Moreover, considering one- and two-dimensional EC patterns, TWs are discussed; they reveal the roles of the ac and noise fields for TWs.

    DOI: 10.1109/ICNF.2017.7986026

    Scopus

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  • Pattern formations in electroconvection by colored noise 査読有り 国際誌

    Y. Yano, J. -H. Huh

    2017 International Conference on Noise and Fluctuations, ICNF 2017   2017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(国際会議プロシーディングス)

    We report noise-induced threshold shifts in ac-driven electroconvection (EC) in nematic liquid crystals (NLCs). It has been known that noise plays a role in stabilization (fc > fc∗) or destabilization (fc < fc∗) effects on EC depending on its cutoff frequencies fc; therefore, these effects monotonically increase (fc > fc∗) or decrease (fc < fc∗) the EC threshold Vc. However, we have found an interesting threshold shift not showing the monotonic behavior for around a characteristic fc∗; this "reversed bell-shaped behavior" implies "inverse stochastic resonance (ISR)". We also were able to observe traveling waves (TWs) in the noise-induced phenomena; basically, TWs are one of the typical EC, which have been well understood in the so-called weak electrolyte model showing a Hopf bifurcation. Considering the characteristic of colored noise (i.e., intensity VN and cutoff frequency fc), ISR and TW are presented and discussed.

    DOI: 10.1109/ICNF.2017.7986028

    Scopus

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  • Traveling waves and worms in ac-driven electroconvection under external multiplicative noise 査読有り 国際誌

    Huh J.

    Physical Review E   95 ( 4 )   2017年04月

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    担当区分:筆頭著者, 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)

    © 2017 American Physical Society.In the presence of external multiplicative noise, ac-driven electroconvection (EC) in a nematic liquid crystal is investigated. Noise-induced traveling waves (TWs) including localized ones (worms) are found with a typical, stationary wave. Three kinds of TWs are classified by their dynamic features (e.g., noise-intensity-dependent Hopf frequency and space-time map). Moreover, ac frequency-dependent threshold voltages of EC are examined in high noise intensities causing abnormal charge redistribution of the EC cell, and the roles of ac and noise fields with respect to TWs are elucidated in successive pattern evolutions. The mechanism of TWs is discussed in terms of a locally perturbed dynamic conductivity due to the noise field additionally applied to the EC; such a conductivity can be related to a weak-electrolyte model for a Hopf bifurcation to a TW.

    DOI: 10.1103/PhysRevE.95.042704

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  • Electrooptical Threshold Behavior of Electroconvection in Twisted Nematic Liquid Crystal Cells 査読有り 国際誌

    Jae Min Song, Gyu-Jin Choi, Jin Seog Gwag,Youngku Sohn, Jong-Hoon Huh

    Journal of the Korean Physical Society   70 ( 3 )   276 - 280   2017年02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)

    In this paper, the electrooptical threshold behavior of electroconvection caused by the electrohydrodynamic instability in twisted nematic liquid crystal cells is presented. We observed the electroconvection optically and analyzed the change in the electrical threshold behavior according to the twisted angles in twisted liquid crystal cells in the conduction region that shows the Williams domain, which is one of the most basic patterns for electroconvection in an anisotropic fluid like liquid crystals (LCs). As a result, we confirmed that in the low frequency conduction regio where the Williams domain appears, the threshold voltage decreased as the twist angle increased even though the twist structure enhanced the effective viscosity in liquid flow. The increase in the twist angle may shorten the charge relaxation time because a twisted LC is a structure that more easily accumulates electrical charges on local curvatures.

    DOI: 10.3938/jkps.70.276

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  • Inverse stochastic resonance in electroconvection by multiplicative colored noise 査読有り 国際誌

    Huh J.

    Physical Review E   94 ( 5 )   2016年11月

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    担当区分:筆頭著者, 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)

    © 2016 American Physical Society.A kind of inverse stochastic resonance (ISR) observed in ac-driven electroconvection (EC) in a nematic liquid crystal is presented. In successive pattern evolutions by increasing noise intensity VN, a typical EC (with a normalized amplitude A0=1 at VN=0) disappears (A0→0), and then the rest state (A0=0) reenters into the EC (A0=1); eventually, it develops into complicated EC(A0>1). The reversed bell-shaped behavior of A0(VN) is evidence of ISR. The present ISR may be explained by taking into account colored noise characterized by its intensity and correlation time.

    DOI: 10.1103/PhysRevE.94.052702

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  • Multiplicative Noise-Induced Electrohydrodynamic Pattern Formations by Controlling Electric Conductivity 査読有り

    Jong-Hoon HUH

    Journal of the Physical Society of Japan   85 ( 2 )   024002   2016年02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: 10.7566/JPSJ.85.024002

    Kyutacar

    Scopus

    CiNii Article

  • Multiplicative noise effects on electroconvections in controlling additive noise by a magnetic field 査読有り

    Jong-Hoon HUH

    Physical Review E   92   062504   2015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)

    主要雑誌 代表的研究業績

    DOI: 10.1103/PhysRevE.92.062504

    Scopus

  • Colored Noise-Induced Threshold Shifts and Phase Diagrams in Electroconvections 査読有り

    Huh Jong-Hoon, Kai Shoichi

    Journal of the Physical Society of Japan ( Physical Society of Japan )   83 ( 6 )   63601 - 1-4   2014年06月

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

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/40020091395

  • Noise-induced threshold shift and pattern formation in electroconvection by controlling characteristic time scales 査読有り

    Jong-Hoon HUH

    Physical Review E   84   025302   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)

    主要雑誌 代表的研究業績

    DOI: 10.1103/PhysRevE.84.025302

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  • Electrohydrodynamic Pattern Formation in Nematic Liquid Crystals by External Pure Noise 査読有り

    Huh Jong-Hoon

    Journal of the Physical Society of Japan ( Physical Society of Japan )   79 ( 12 )   123602 - 123602   2010年12月

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

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/210000108604

  • Electrohydrodynamic Pattern Formation in Nematic Liquid Crystals by External Pure Noise 査読有り

    許 宗焄

    Journal of the Physical Society of Japan (Letter)   79 ( 12 )   123602.1 - 123602.4   2010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)

    主要雑誌 代表的研究業績

    DOI: 10.1143/JPSJ.79.123602

    Scopus

    CiNii Article

  • Noise-controlled pattern formation and threshold shift for electroconvections in conduction and dielectric regimes 査読有り

    Jong-Hoon HUH,Akiyuki KURIBAYASHI,and Shoichi KAI

    Physical Review E   80 ( 1 )   066304.1 - 066304.9   2009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)

    主要雑誌 代表的研究業績

    Kyutacar

  • Noise-controlled pattern formation and threshold shift for electroconvection in the conduction and dielectric regimes 査読有り

    Huh J., Kuribayashi A., Kai S.

    Physical Review E - Statistical, Nonlinear, and Soft Matter Physics   80 ( 6 )   2009年12月

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

    We report noise-controlled electrohydrodynamic pattern formations and threshold shifts in nematic liquid crystals. In the electrohydrodynamic system superposed with noise, experimental results obtained in the dielectric regime are compared to those in the conventional conduction regime. The noise intensity dependences of thresholds and pattern evolution processes are remarkably different for each regime. The pattern formation mechanisms in the presence of noise for both regimes are discussed based on the results. Moreover, it is found that the thresholds and characteristic wavelengths of dissipative structures can be effectively controlled by external multiplicative noises with appropriate intensity and correlation times. © 2009 The American Physical Society.

    DOI: 10.1103/PhysRevE.80.066304

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  • Difference in Noise-Induced Threshold Shift between Planar and Homeotropic Electroconvections in Nematic Liquid Crystals 査読有り

    Huh Jong-Hoon, Kuribayashi Akiyuki, Kai Shoichi

    Journal of the Physical Society of Japan ( Physical Society of Japan )   78 ( 8 )   83601 - 83601   2009年08月

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

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/210000107903

  • Difference in noise-induced threshold shift between planar and homeotropic electroconvections in nematic liquid crystals 査読有り

    Huh J., Kuribayashi A., Kai S.

    Journal of the Physical Society of Japan ( 一般社団法人 日本物理学会 )   78 ( 8 )   83601 - 83601   2009年08月

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

    We report the threshold shift induced by externally applied noises for electrohydrodynamic convections (EHCs) in both planarly and homeotropically aligned nematic liquid crystals as well as in both the conduction and dielectric regimes. Owing to the difference in timescales among the intrinsic properties of EHCs, externally applied noises, and deterministic fields, the stabilization or destabilization effects induced by noises are observed. In particular, the difference in the threshold shift between both alignments is found, and discussed in terms of the EHC mechanisms for both alignments. Moreover, a noticeable noise-induced threshold shift is observed in the dielectric regime, which is markedly different from that in the conventional conduction regime. © 2009 The Physical Society of Japan.

    DOI: 10.1143/JPSJ.78.083601

    Scopus

    CiNii Article

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  • Pure Noise-Induced Pattern Formations in a Nematic Liquid Crystal 査読有り

    Huh Jong-Hoon, Kai Shoich

    Journal of the Physical Society of Japan ( Physical Society of Japan )   78 ( 4 )   43601 - 43601   2009年04月

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

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/210000107753

  • Pure noise-induced pattern formations in a nematic liquid crystal 査読有り

    Jong-Hoon Huh,Shoichi Kai

    Journal of the Physical Society of Japan (Letter)   78 ( 4 )   43601.1 - 043601.4   2009年04月

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

    主要雑誌 代表的研究業績

    DOI: 10.1143/JPSJ.78.043601

  • Noise Effects on Threshold of Electrohydrodynamic Convection in Nematic Liquid Crystals 査読有り

    Huh Jong-Hoon, Kai Shoichi

    Journal of the Physical Society of Japan ( 一般社団法人日本物理学会 )   77 ( 8 )   "83601 - 1"-"83601-4"   2008年08月

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

    New experimental aspects of multiplicative noise effects on the onset of ac-driven electroconvection in nematic liquid crystals are presented. In the superposition of a stochastic field with a deterministic one, the variation in the threshold voltage V_c (of the deterministic one) was investigated as a function of the intensity (V_N), cutoff frequency (f_c), and correlation time(τ_N)of the stochastic noise. In particular, it is observed that the noise effects vanish for certain stochastic and deterministic conditions.

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110006914817

  • Noise Effects on Threshold of Electrohydrodynamic Convection in Nematic Liquid Crystals 査読有り

    Jong-Hoon Huh,Shoichi Kai

    Journal of the Physical Society of Japan (Letter)   77 ( 8 )   083601.1 - 083601.4   2008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)

    代表的研究業績

  • Electrohydrodynamic Instability in Cholesteric Liquid Crystals in the Presence of a Magnetic Field 査読有り

    許 宗焄

    Molecular Crystals and Liquid Crystals   477   561 - 570   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)

    主要雑誌

    Kyutacar

  • Noise-induced Electrohydrodynamic Patterns in Nematic Liquid Crystals 査読有り

    Huh Jong-Hoon

    Journal of the Physical Society of Japan ( 一般社団法人日本物理学会 )   76 ( 3 )   "33001 - 1"-"33001-4"   2007年03月

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

    We report on noise-induced patterns and threshold characteristics for the ac-driven electrohydrodynamic system in nematic liquid crystals. The wave number-dependence of the threshold for the stochastic system was experimentally investigated with controlling intensity rate of noise. The results are discussed in comparison with the previous experimental and theoretical ones. Moreover, unexpected patterns as well as pre-transitional ones are presented.

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110006240180

  • Noise-induced Electrohydrodynamic Patterns in Nematic Liquid Crystals 査読有り

    許 宗焄

    Journal of the Physical Society of Japan (Letter) Vol.76, No. 3, pp. 033001, 2007.   76 ( 3 )   033001.1 - 033001.4   2007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)

    代表的研究業績

  • Electrohydrodynamic instability in cholesteric liquid crystals in the presence of a magnetic field 査読有り

    Huh J.

    Molecular Crystals and Liquid Crystals   477 ( 1 )   67 - 76   2007年01月

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

    We report electrohydrodynamic instability in a cholesteric liquid crystal - a mixture of p-methoxy benzylidene p-n-butylaniline (MBBA) and a cholesteric dopant cholesteryl nonanoate (CN), in the presence of a superimposed magnetic field H. We have found a certain intensity H* with respect to the instability in this mixture with negative dielectric anisotropy, beyond which a stripe pattern appears. With an increasing electric field, the stripe pattern evolves into a grid pattern (GP). Investigations of the H-dependences of thresholds and wavelengths for these patterns in comparison with those of nematic liquid crystals clearly show that the typical GPs found in cholesteric liquid crystals are a superposition of two kinds of stripe patterns induced by the electrohydrodynamic instability.

    DOI: 10.1080/15421400701678444

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  • Threshold Characteristics of Electrohydrodynamic Instability in Nematic Liquid Crystals under a Superimposing Magnetic Field 査読有り

    Jong-Hoon Huh,Tetsuji Suenaga

    Colloids and Surfaces A   285 ( 1 )   627 - 630   2006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)

    代表的研究業績

  • Threshold characteristics of electrohydrodynamic instability in nematic liquid crystals under a superimposing magnetic field 査読有り

    Huh J., Suenaga T.

    Colloids and Surfaces A: Physicochemical and Engineering Aspects   284-285   627 - 630   2006年08月

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

    We reported about AC-driven electrohydrodynamic instability in nematic liquid crystals. The characteristics of the threshold field for instability were investigated in Hele-Shaw type cells. We found a remarkable threshold change in the presence of a superimposing magnetic field, which plays a role in suppressing instability. We discuss force competition between the electric field causing the instability and the magnetic field suppressing the instability. Compared to the top-view type cells, moreover, the characteristics of the instability found in the present Hele-Shaw (side-view) cells are discussed. © 2005 Elsevier B.V. All rights reserved.

    DOI: 10.1016/j.colsurfa.2005.11.051

    Scopus

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  • Low voltage-driven electromechanical effects of swollen liquid crystal elastomers 査読有り

    Yusril Yusuf,Jong-Hoon Huh,P. E. Cladis,H. R. Brand,H. Finkelmann,Shoichi Kai

    Physical Review E   71 ( 6 )   061702.1 - 061702.8   2005年06月

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  • Low-voltage-driven electromechanical effects of swollen liquid-crystal elastomers 査読有り

    Yusuf Y., Huh J., Cladis P., Brand H., Finkelmann H., Kai S.

    Physical Review E - Statistical, Nonlinear, and Soft Matter Physics   71 ( 6 )   2005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)

    We experimentally investigate, in detail, electromechanical effects in liquid-crystal elastomers (LCEs) previously swollen with low-molecular-weight liquid crystals (LMWLCs). Both polydomain (POLY) and monodomain (MONO) LCEs were studied. We used a well known LMWLC, 4-n-pentyl-4-cyanobiphenyl (5CB) as a solvent. After swelling POLY and MONO LCEs (LSCE) with 5CB, shape changes were measured by recording the displacement of the edge of the swollen LCE at different voltages, V, and temperature. With 100μm distance between electrodes, measurable shape changes (∼1-20μm) are observed with small voltages (V∼0.5-10V). In particular, we note that, compared to unswollen L(S)CEs, a dramatic ∼200 times decrease of the threshold field was found for electromechanical effects in swollen L(S)CEs. While swollen MONO LCEs showed electromechanical effects in the planar geometry, homeotropic MONO swollen with homeotropically oriented 5CB did not. This is easy to understand because, in the homeotropic case, the liquid-crystal preferred axis is already aligned with the field so the field has no reorienting effect. The inverse of the response time when the field was switched on in both POLY and MONO was proportional to E2, which is the same field dependence as the response time of LMWLCs. When the field was switched off, the relaxation time showed a field dependence different from that of LMWLCs that we attribute to relaxation of the LCE network. © 2005 The American Physical Society.

    DOI: 10.1103/PhysRevE.71.061702

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  • Temperature Dependence of Electromechanical Effects in a Swollen Polydomain Liquid Crystalline Elastomer 査読有り

    Jong-Hoon Huh,Jiang Xin,Yusril Yusuf,Shoichi Kai

    Journal of the Physical Society of Japan   74 ( 1 )   242 - 245   2005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)

    代表的研究業績

  • Temperature dependence of electromechanical effects in a swollen polydomain liquid crystalline elastomer 査読有り

    Huh J., Xin J., Yusuf Y., Kai S.

    Journal of the Physical Society of Japan ( 一般社団法人 日本物理学会 )   74 ( 1 )   242 - 245   2005年01月

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

    We report electromechanical effects in a swollen polydomain liquid crystalline elastomer (POLY-LCE). Owing to the director reorientation, we could directly observe its deformation in the unconstrained elastomer gel state. Using optical image analysis, the deformation amplitude, threshold voltage, and temporal characteristics of the POLY-LCE were quantitatively measured with varying voltage and temperature. From the experimental results we discuss the deformation mechanism and property of the POLY-LCE. ©2005 The Physical Society of Japan.

    DOI: 10.1143/JPSJ.74.242

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  • A periodic director structure of nematic liquid crystals in a high- frequency electric field 査読有り

    Huh J., Yusuf Y., Hidaka Y., Kai S.

    Molecular Crystals and Liquid Crystals   410   2004年12月

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    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)

    We report an electrohydrodynamic instability, the prewavy instability, in nematic liquid crystals in a high-frequency electric field. This instability shows isotropic feature, zigzag flows, and constant spatial periodicity with respect to the amplitude and frequency of the applied electric field. It should be distinguished from similar instabilities such as the isotropic electrolyte mode, the inertia mode and the dielectric mode reported already.

    DOI: 10.1080/15421400490434586

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  • New characteristics of electrohydrodymanic instability in a nematic liquid crystal doped with a cholesteric one 査読有り

    Jong-Hoon Huh,Yoichi Akasako,Shoichi Kai

    Journal of the Physical Society of Japan   73 ( 11 )   2975 - 2978   2004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)

    代表的研究業績

  • New Characteristics of Electrohydrodynamic Instability in a Nematic Liquid Crystal Doped with a Cholesteric One 査読有り

    Huh Jong-Hoon, Akasako Yoichi, Kai Shoichi

    Journal of the Physical Society of Japan ( 一般社団法人日本物理学会 )   73 ( 11 )   2975 - 2978   2004年11月

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

    We report electroconvection in a cholesteric liquid crystal with negative dielectric anisotropy, that is, a mixture of <I>p</I>-methoxy benzilidene <I>p</I>-<I>n</I>-butylaniline (MBBA) with a small amount of a cholesteric dopant cholesteryl nonanoate (CN). By changing the corresponding helical pitch by varying the concentration of CN, a variety of ac-driven convective patterns are found in sandwiched sample cells. The pitch and temperature dependences of their threshold voltages and characteristic wavelength of the patterns are systematically investigated.

    DOI: 10.1143/jpsj.73.2975

    CiNii Article

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  • New characteristics of electrohydrodynamic instability in a nematic liquid crystal doped with a cholesteric one 査読有り

    Huh J., Akasako Y., Kai S.

    Journal of the Physical Society of Japan   73 ( 11 )   2975 - 2978   2004年11月

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

    We report electroconvection in a cholesteric liquid crystal with negative dielectric anisotropy, that is, a mixture of p-methoxy benzilidene p-n-butylaniline (MBBA) with a small amount of a cholesteric dopant cholesteryl nonanoate (CN). By changing the corresponding helical pitch by varying the concentration of CN, a variety of ac-driven convective patterns are found in sandwiched sample cells. The pitch and temperature dependences of their threshold voltages and characteristic wavelength of the patterns are systematically investigated. © 2004 The Physical Society of Japan.

    DOI: 10.1143/JPSJ.73.2975

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  • A periodic director structure of nematic liquid crystals in a high-frequency electric field 査読有り

    Jong-Hoon Huh,Yoshiki Hidaka,Yusril Yusuf,Shoichi Kai

    Molecular Crystals and Liquid Crystals   410   567 - 575   2004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)

  • Electroconvection in nematic liquid crystals in Hele-Shaw cells 査読有り

    Jong-Hoon HUH,Shoichi KAI

    Physical Review E   68 ( 4 )   042702.1 - 042702.4   2003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)

  • Thermo and electro properties of a nematic elastomer in a liquid crystal

    許 宗焄

    JLCS2003 (2003年日本液晶学会会計討論会 講演予稿集)   355 - 356   2003年04月

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    記述言語:日本語   掲載種別:研究論文(その他学術会議資料等)

  • ネマチック液晶におけるprewavy不安定性 (複雑流体の数理3 研究集会報告書)

    日高 芳樹, Yusuf Yusril, Huh Jong-Hoon, 甲斐 昌一

    数理解析研究所講究録 ( 京都大学数理解析研究所 )   ( 1305 )   122 - 130   2003年02月

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    記述言語:英語   掲載種別:研究論文(研究会,シンポジウム資料等)

    CiNii Article

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  • Electroconvection in nematic liquid crystals in Hele-Shaw cells 査読有り

    Huh J., Kai S.

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics   68 ( 4 )   2003年01月

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

    We report electrohydrodynamic instability in nematic liquid crystals found in Hele-Shaw cells. Due to the present cell geometry, the convective structures could be directly visualized as surface or bulk flows. An unexpected structure is observed, which is completely different from the well-known patterns in the standard cells. By using the voltage-frequency jump method, the stability of a convective structure in Hele-Shaw cells is discussed in terms of the Busse diagram. © 2003 The American Physical Society.

    DOI: 10.1103/PhysRevE.68.042702

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  • PA31 液晶エラストマの温度・電気特性(物理・物性)

    許 宗焄, 甲斐 昌一

    日本液晶学会討論会講演予稿集 ( 日本液晶学会 )   2003 ( 0 )   355 - 356   2003年01月

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    担当区分:筆頭著者   記述言語:英語   掲載種別:研究論文(研究会,シンポジウム資料等)

    Electro-mechanical effects for a swelling liquid crystalline elastomer have been investigated. Due to the director reorientation, its deformation has been directly observed in unconstrained elastomer gel states. By using an optical image analysis, the amplitude and characteristic times of its deformation have been quantitatively measured with changing voltage and temperature.

    DOI: 10.11538/ekitou.2003.0_355

    CiNii Article

    その他リンク: https://ci.nii.ac.jp/naid/110001482339

  • Prewavy instability of nematic liquid crystals in a high-frequency electric field 査読有り

    Huh J., Yusuf Y., Hidaka Y., Kai S.

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics   66 ( 3 )   2002年09月

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

    A kind of electrohydrodynamic instability, the prewavy instability, in nematic liquid crystals is reported. The characteristic of the instability was optically investigated and discussed in comparison with some similar instabilities. Obviously the instability partially shows an isotropic feature around the nematic-isotropic transition temperature. Owing to the characteristic properties of the flow and the spatial periodicity, it should be distinguished from a previously proposed isotropic instability. © 2002 The American Physical Society.

    DOI: 10.1103/PhysRevE.66.031705

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  • Prewavy instability of nematic liquid crystals in a high-frequency electric field 査読有り

    Jong-Hoon Huh,Yusril Yusuf,Yoshiki Hidaka,Shoichi Kai

    Physical Review E   66 ( 3 )   031705.1 - 031705.6   2002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)

  • New Classification of Chevrons in Electroconvection in Homeotropically-Aligned Nematics 査読有り

    Jong-Hoon Huh,Yoshiki Hidaka,and Shoichi Kai

    MOL. CRYST. LIQ. CRYST.   366 ( 1 )   2685 - 2692   2001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)

  • Prewavy pattern: a director-modulation structure in nematic liquid crystals 査読有り

    Jong-Hoon Huh,Yoshiki Hidaka (Kyushu Univ),Yusril Yusuf (Kyushu Univ),Nandor Eber (RISSPO of Budapest),Tibor Toth-Katona (RISSPO),Agnes Buka (RISSPO),and Shoichi Kai (Kyushu Univ)

    MOL. CRYST. LIQ. CRYST.   364 ( 1 )   111 - 122   2001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)

  • Prewavies: a Director-Modulation Pattern in Nematic Liquid Crystals 査読有り

    許 宗焄

    Molecular Crystals and Liquid Crystals   364   111 - 122   2001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)

  • New Classification of Chevrons in Electroconvection in Homeotropically-Aligned Nematics 査読有り

    許 宗焄

    Molecular Crystals and Liquid Crystals   366   2685 - 2692   2001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)

  • New classification of chevrons in electroconvection in homeotropically-aligned nematics 査読有り

    Huh J., Hidaka Y., Kai S.

    Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals   366   833 - 840   2001年01月

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

    Two types of chevrons have been found in the conduction regime, as well as the conventional chevrons in the dielectric regime in homeotropically-aligned nematics. These two are named the defect-mediated chevron (DMC) and the defect-free chevron (DFC) by their structure changes. Two different bifurcation sequences are found with increasing the applied voltage, such as Fréedericksz transition → normal rolls → abnormal rolls → defect chaos →DMC for low frequencies and Fréedericksz transition → prewavy pattern → DFC for high frequencies. Moreover, the double periodicity of the chevrons (i.e., the short wavelength λ1 of the striated rolls and the long wavelength λ2 of the chevron bands) shows quite specific frequency dependence. © 2001 OPA (Overseas Publishers Association) N.V. Published by license under the Gordon and Breach Science Publishers imprint, a member of the Taylor & Francis Group.

    DOI: 10.1080/10587250108024024

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  • Prewavy pattern: A director-modulation structure in nematic liquid crystals 査読有り

    Huh J., Hidaka Y., Yusuf Y., Éber N., Tóth-Katona T., Buka A., Kai S.

    Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals   364   111 - 122   2001年01月

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

    A periodic structure (the prewavy pattern) found below the onset of electroconvection in a homeotropically aligned nematic liquid crystal is reported. It is characterized by a periodic modulation of the director in the xy-plane, which can be distinguished from electroconvection patterns with modulation in the xz-plane. The prewavy instability is investigated in detail; a phase diagram in the frequency-voltage plane, the voltage dependence of the azimuthal rotation angle, the voltage and frequency dependence of the wavelength of the prewavy pattern, and the director field in the prewavy pattern are provided. This prewavy pattern always evolves into the so-called chevrons above onset of convection. The wavelength of the chevrons and the orientation of their alternating zig and zag rolls depend on the director structure of the prewavy pattern. © 2001 OPA (Overseas Publishers Association) N.V. Published by licence under the Gordon and Breach Science Publishers imprint, Taylor & Francis Group,.

    DOI: 10.1080/10587250108024981

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  • Pattern formation of chevrons in conduction regime in homeotropically aligned liquid crystals 査読有り

    許 宗焄

    Pysical Review E   61 ( 3 )   2769 - 2776   2000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)

  • Pattern formation of chevrons in the conduction regime in homeotropically aligned liquid crystals 査読有り

    Huh J., Hidaka Y., Rossberg A., Kai S.

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics   61 ( 3 )   2769 - 2776   2000年01月

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

    We report on chevrons (herringbonelike patterns) observed in homeotropically aligned liquid crystals with high electric conductivity. We focus our attention on two types of chevrons observed in the conduction regime. The threshold voltage and the characteristic double periodicity of chevrons (i.e., the short wavelength [Formula Presented] of the striated rolls and the long wavelength [Formula Presented] of the chevron bands) have been measured as functions of the applied electric frequency f. With the aid of a crossed polarizer set, we have, in addition, determined the director field which shows a periodic in-plane rotation for our chevrons (with a wavelength [Formula Presented] We arrived at the types of chevrons after qualitatively different bifurcation sequences with increasing voltage. The frequency dependence of [Formula Presented] also shows a qualitatively different behavior with respect to the two types of chevrons. The experimental results are discussed in terms of recent theoretical investigations. © 2000 The American Physical Society.

    DOI: 10.1103/PhysRevE.61.2769

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  • New Scenario to Spatio-Temporal Chaos in Normal Rolls Regime with Magnetic Field in Electroconvection of Homeotropic Nematics 査読有り

    許 宗焄

    Molecular Crystals and Liquid Crystals   328   497 - 504   1999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)

  • Formation Scenarios for Nonlinear Patterns in Electroconvection under controlling Goldstone Modes by Magnetic Field 査読有り

    許 宗焄

    Journal of the Physical Society of Japan   68 ( 5 )   1567 - 1577   1999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)

  • Formation scenarios for nonlinear patterns in electroconvection under controlling goldstone modes in magnetic field 査読有り

    Huh J., Hidaka Y., Kai S.

    Journal of the Physical Society of Japan   68 ( 5 )   1567 - 1577   1999年05月

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

    We report novel scenarios for the transitions from a stationary periodic state to spatio-temporal chaos (STC) for electroconvection in homeotropically aligned nematics, in which a constant magnetic field H is applied perpendicularly to an electric field. Above a characteristic frequency fL(in the normal roll regime), when increasing the applied electric field, stationary periodic roll patterns become unstable, and evolve to STC at a certain electric field. For f > fLwe find the second stationary periodic roll pattern (i.e., abnormal rolls) at higher electric fields for H > H*, where H* is a characteristic magnetic intensity. At much higher electric field the reentrant stationary periodic rolls evolve to STC again. Reentrant stationary rolls are not observed for H < H*. Below fL(in the oblique roll regime), on the other hand, with increasing the electric field, stationary periodic rolls also become unstable toward STC. In the oblique roll regime, however, we find no reentrant stationary rolls below and above H*. The abnormal roll instability responsible for the reentrant rolls corresponds to a homogeneous azimuthal rotation of the director and plays important role for the novel scenarios. Based on systematic studies, we have determined phase diagrams in the H - ε plane, where ε is a normalized electric voltage.

    DOI: 10.1143/JPSJ.68.1567

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  • 液晶の電気流体力学的不安定性におけるシェブロン・パターンの多様性

    許 宗焄

    数理解析研究所講究録 複雑流体の数理   1081   19 - 29   1999年04月

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    記述言語:日本語   掲載種別:研究論文(大学,研究機関等紀要)

  • Novel Pattern Transition Scenarios in Electrconvection in Homeotropic Nematics under Magnetic Field

    許 宗焄

    RIMS Kokyuroku Mathematical Aspects of Complex Fluids   1081   10 - 18   1999年04月

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    記述言語:英語   掲載種別:研究論文(大学,研究機関等紀要)

  • New Scenario to Spatio-Temporal Chaos in Normal Rolls Regime with Magnetic Field in Electroconvection of Homeotropic Nematics 査読有り

    Huh J., Hidaka Y., Kai S.

    Molecular Crystals and Liquid Crystals Science and Technology Section A: Molecular Crystals and Liquid Crystals   328   497 - 504   1999年01月

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

    We report a new transition scenario from a uniform state to the spatio-temporal chaos (STC) for the electroconvection in the homeotropically aligned nematics, in which a magnetic field is applied perpendicularly to the electric field. Above the Lifshitz frequency fL the amplitude of the electric field increasing, a stationary periodic rolls state becomes unstable, then evolves to STC-I (i.e., the defect chaos) at a certain electric field. At a higher electric field, the second stationary periodic rolls (i.e., abnormal rolls) are also found above a characteristic intensity of the magnetic field H*. At further higher electric field the second stationary periodic rolls state becomes unstable again, then evolves to more complicated STC (STC-II). Above H* the abnormal rolls instability corresponding to an azimuthal rotation of the director plays key roles on the pattern transitions between stationary and non-stationary states as well as between the two stationary ones. Based on the systematic study, a clear phase diagram was determined in the H-ε plane. These results are remarkably different from ones below fL previously reported.

    DOI: 10.1080/10587259908026093

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  • Transition Properties of the Soft-Mode Turbulence in the Homeotropic Electroconvection Superimposing Magnetic Fields 査読有り

    許 宗焄

    Journal of the Physical Society of Japan   67 ( 6 )   1948 - 1954   1998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)

  • Transition properties of the soft-mode turbulence in the homeotropic electro convection superimposing magnetic fields 査読有り

    Huh J., Hidaka Y., Kai S.

    Journal of the Physical Society of Japan   67 ( 6 )   1948 - 1954   1998年06月

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

    The experimental study on transition processes of the spatio-temporal chaos (STC) as well as periodic patterns in homeotropically aligned nematic liquid crystals is reported under superimposing magnetic fields with electric fields. The strong dependence of the threshold for STC on the strength of magnetic fields is observed above certain normalized voltage εth, where the two types of STC are found out below and beyond the characteristic value of the magnetic field H* = 620 G. The periodic patterns were observed for the normalized voltage ε below εth. Below H* the soft-mode turbulence appears due to the Goldstone mode related to a continuous rotational-symmetry which can be controlled by the application of H. Beyond H*, the conventional STC called defect turbulence, which is similar to STC in the planar system, is observed.

    DOI: 10.1143/JPSJ.67.1948

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  • Observation and determination of abnormal rolls and abnormal zigzag rolls in electroconvection in homeotropic liquid crystals 査読有り

    Huh J., Hidaka Y., Kai S.

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics   58 ( 6 )   7355 - 7358   1998年01月

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

    Direct evidence for two different types of normal rolls and of zigzag rolls in homeotropically aligned nematic liquid crystals in a magnetic field is reported. The conventional normal rolls have the reflection symmetry in the xy plane. The instability, however, breaks the reflection symmetry [Formula Presented] on the director and then the abnormal rolls are expected to be observed. We have investigated the instability experimentally and discussed it in terms of the recent numerical results by Plaut et al. [Phys. Rev. Lett. 79, 2367 (1997)]. Due to the new instability, the abnormal zigzag rolls are also found below the Lifshitz frequency. © 1998 The American Physical Society.

    DOI: 10.1103/PhysRevE.58.7355

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0001245826&origin=inward

  • Soft-Mode Turbulence in Electrohydrodynamic Convection of a Homeotropically Aligned Nematic Layer 査読有り

    許 宗焄

    Physical Review E   56 ( 6 )   R6256 - R6259   1997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)

  • Dynamical Aspects of Spatiotemporal Chaos at the Onset of Electroconvection in Homeotropic Nematics 査読有り

    許 宗焄

    Journal of the Physical Society of Japan   66 ( 11 )   3329 - 3332   1997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)

  • Dynamical Aspects of Spatiotemporal Chaos at the Onset of Electroconvection in Homeotropic Nematics 査読有り

    Hidaka Y., Huh J., Hayashi K., Kai S., Tribelsky M.

    Journal of the Physical Society of Japan   66 ( 11 )   3329 - 3332   1997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 systematic experimental study of direct transition “nonconvective state — spatiotemporal chaos” in electrohydrodynamic convection of a homeotropically aligned nematic is carried out. The transient patterns, both below and beyond the Lifshitz point, are studied and classified. The patterns initially correspond to oblique and normal rolls, respectively. In all the cases the transition to chaos undergoes slow spatiotemporal modulations of the local roll orientation. This results in the final dynamical patterns isotropic on large spatial scales. The dynamics of the final patterns are also studied with a quantitative analysis of the power spectra of turbulent modes and their autocorrelation functions. The exponential decay of the correlations in time is proved. © 1997, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.

    DOI: 10.1143/JPSJ.66.3329

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=33644692179&origin=inward

  • Soft-mode turbulence in electrohydrodynamic convection of a homeotropically aligned nematic layer 査読有り

    Hidaka Y., Huh J., Hayashi K., Kai S., Tribelsky M.

    Physical Review E - Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics   56 ( 6 )   R6256 - R6259   1997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 experimental study of electroconvection in a homeotropically aligned nematic (MBBA) is reported. The system undergoes a supercritical bifurcation “rest state-spatiotemporal chaos.” The chaos is caused by long-wavelength modulation of the orientation of convective rolls. For the first time the observations both below and beyond the Lifshitz point are accompanied by quantitative analysis of temporal autocorrelation functions of turbulent modes. The dependence of the correlation time on the control parameter is obtained. A secondary bifurcation from normal to abnormal rolls is discussed. © 1997 The American Physical Society.

    DOI: 10.1103/PhysRevE.56.R6256

    Scopus

    その他リンク: https://www.scopus.com/inward/record.uri?partnerID=HzOxMe3b&scp=0001234479&origin=inward

  • ゾル・ゲル転移過程におけるヘレーショウセル中のパターン形成

    許 宗焄

    九州大学工学集報   69 ( 4 )   425 - 429   1996年04月

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    記述言語:日本語   掲載種別:研究論文(大学,研究機関等紀要)

▼全件表示

著書

  • 情報工学基礎実験

    小田部荘司,小松英樹,宮瀬紘平,李旻哲,清水文雄,許 宗焄(共著)

    学術図書出版社  2018年09月  ( ISBN:978-4-7806-0664-5

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    記述言語:日本語

口頭発表・ポスター発表等

  • 液晶電気対流におけるノイズの影響

    塩見雅人,許 宗焄

    第127回日本物理学会九州支部例会  日本物理学会九州支部

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    開催期間: 2021年12月04日   記述言語:日本語   開催地:Online  

  • 液晶電気対流系における制御された外乱の効果

    宮川 直人,塩見 雅人,許 宗焄

    西日本非線形科学研究会 

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    開催期間: 2020年07月18日   記述言語:日本語   開催地:ONLINE  

  • 誘電領域の電気対流現象の調査

    塩見 雅人,宮川 直人,許 宗焄

    西日本非線形科学研究会 

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    開催期間: 2020年07月18日   記述言語:日本語   開催地:ONLINE  

  • サイクロンセパレータ内部の数値シミュレーション

    志波昇昭

    日本機械学会九州学生会第47回卒業研究発表講演会  日本機械学会九州学生会

     詳細を見る

    開催期間: 2016年03月04日   記述言語:日本語   開催地:鹿児島  

  • 散水管の流動特性の導出

    松吉祐弥

    日本機械学会九州学生会第47回卒業研究発表講演会  日本機械学会九州学生会

     詳細を見る

    開催期間: 2016年03月04日   記述言語:日本語   開催地:鹿児島  

  • Electrohydrodynamic Instability Problem by Controlling Internal and External Characteristic Times

    JONG-HOON HUH

    The 2nd Asian Conference on Liquid Crystals (ACLC2015) 

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    開催期間: 2015年01月19日 - 2015年01月21日   記述言語:英語   開催地:Busan, Korea  

  • Stochastic Matching between Internal and External Timescales in Electroconvection

    Jong-Hoon Huh

    The 2nd International Symposium on Multi-scale Simulations of Biological and Soft Materials (MSBSM 2011) 

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    開催期間: 2011年09月10日 - 2011年09月12日   記述言語:英語   開催地:Kyoto, Japan  

  • Response of electrohydrodynamic convection to external noise

    Jong-Hoon Huh,Xiangwen Cui

    The 21st International Conference on Noise and Fluctuation (ICNF2011) 

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    開催期間: 2011年06月12日 - 2011年06月16日   記述言語:英語   開催地:Toronto, Canada  

  • Electrohydrodynamic instability in cholesteric liquid crystals under controlling helical pitch

    本人

    The 21th International Liquid Crystal Conference(ILCC2006)  

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    開催期間: 2006年07月02日 - 2006年07月07日   記述言語:英語   開催地: America Keystone, Colorado  

  • Threshold Characteristics of Electrohydrodynamic Instability in Nematic Liquid Crystals under a Superimposing Magnetic Field

    本人

    The 11th International Conference on Organized Molecular Films (LB11) 

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    開催期間: 2005年06月26日 - 2005年06月30日   記述言語:英語   開催地:日本 Hokkaido  

  • Thermo and electro properties of a nematic elastomer in a liquid crystal

    日本液晶学会討論会(JLCS 2003) 

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    開催期間: 2003年10月14日 - 2003年10月17日   記述言語:英語   開催地: 青森  

  • ネマティック液晶における新しい配向構造とそのメカニズム

    日本物理学会2002年秋季大会 

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    開催期間: 2002年09月06日 - 2002年09月09日   記述言語:日本語   開催地: 中部大学  

  • A periodic director structure of nematic liquid crystals in a high-frequency electric field

    The 19th International Liquid Crystal Conference(ILCC2002) 

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    開催期間: 2002年06月30日 - 2002年07月05日   記述言語:英語   開催地: Edinburgh, Scotland  

  • Long Wavelength Patterns in Electroconvecting Nematics

    The 6th European Conference on Liquid Crystals (ECLC 2001) 

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    開催期間: 2001年03月25日 - 2001年03月30日   記述言語:英語   開催地: Halle (Saale), Germany  

  • New Classification of Chevrons in Electroconvection in Homeotropically-Aligned Nematics

    The 18th International Liquid Crystal Conference(ILCC2000) 

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    開催期間: 2000年07月24日 - 2000年07月28日   記述言語:英語   開催地: Sendai, Japan  

  • Goldstone Modeの関与した時空カオス

    複雑系:理論と新技術 -人文・社会科学,工学,自然科学の交流 

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    開催期間: 2000年05月25日 - 2000年05月26日   記述言語:日本語   開催地: 早稲田大学  

  • ゴールドストーン・モードの関与した時空カオス

    「反応拡散系:生物、化学における現象とモデル」の研究会 

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    開催期間: 2000年04月25日 - 2000年04月27日   記述言語:日本語   開催地: 京大物理  

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講演

  • Noise-controlled electrohydrodynamic instability in a nematic liquid crystal

    The 13th International Meetting on Information (IMID2013)  2013年08月 

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    開催期間: 2013年08月25日 - 2013年08月29日   発表言語:英語   講演種別:特別講演   開催地:Daegu, Korea  

  • Response of electrohydrodynamic convections to noise

    A symposium in the honor of Shoichi Kai   2013年02月 

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    開催期間: 2013年02月23日   発表言語:英語   講演種別:特別講演   開催地:Fukuoka, Japan  

学術関係受賞

  • Award (JPSJ Papers of Editors' Choice)

    The Physical Society of Japan   2014年05月

    Jong-Hoon Huh, Shoichi Kai

     詳細を見る

    受賞国:日本国

科研費獲得実績

  • カラーノイズによる液晶対流系の制御

    研究課題番号:15K05215  2015年04月 - 2018年03月   基盤研究(C)

  • 液晶対流系における散逸構造のノイズ応答性

    研究課題番号:22540394  2010年10月 - 2013年03月   基盤研究(C)

  • e-ラーニングを用いた物理リメディアル教育の実践

    研究課題番号:19300263  2007年04月 - 2011年03月   基盤研究(B)

  • ネマティック液晶系におけるノイズ効果

    研究課題番号:18540377  2006年04月 - 2009年03月   基盤研究(C)

  • 課題探求を指向する実験学習の支援システムに関する研究

    研究課題番号:16300273  2004年04月 - 2007年03月   基盤研究(B)

  • 液晶ゲルの人工筋肉への応用研究

    研究課題番号:16560011  2004年04月 - 2006年03月   基盤研究(C)

  • ネマティック液晶における新しい配向構造の発生メカニズムに関する研究

    研究課題番号:13750017  2001年04月 - 2003年03月   奨励研究(A)→若手研究(B)

▼全件表示

担当授業科目(学内)

  • 2023年度   情報物性特論EP

  • 2023年度   科学技術日本語

  • 2023年度   情報工学基礎実験

  • 2023年度   電磁気学Ⅰ

  • 2023年度   力学Ⅰ

  • 2022年度   学際情報講究Ⅱ

     詳細を見る

    科目区分:大学院専門科目

  • 2022年度   マイクロ・ナノシステム技術特論EP

     詳細を見る

    科目区分:大学院専門科目

    マイクロ・ナノシステム技術の実験実習(集中講義)

  • 2022年度   情報物性特論BP

  • 2022年度   情報物性特論EP

  • 2022年度   科学技術日本語

  • 2022年度   情報工学基礎実験

  • 2022年度   電磁気学Ⅰ

  • 2022年度   力学Ⅰ

  • 2021年度   科学技術日本語

  • 2021年度   情報工学基礎実験

  • 2021年度   電磁気学Ⅰ

  • 2021年度   力学Ⅰ

  • 2020年度   情報物性特論

  • 2020年度   情報工学基礎実験

  • 2020年度   電磁気学Ⅰ

  • 2020年度   力学Ⅰ

  • 2019年度   科学技術日本語

  • 2019年度   科学技術日本語B

  • 2019年度   科学技術日本語A

  • 2019年度   情報工学基礎実験

  • 2019年度   電磁気学Ⅰ

  • 2019年度   力学Ⅰ

  • 2018年度   情報物性特論

  • 2018年度   機械情報基礎

  • 2018年度   電磁気学

  • 2018年度   力学

  • 2018年度   情報工学基礎実験

  • 2018年度   電磁気学Ⅰ

  • 2018年度   力学Ⅰ

  • 2017年度   科学技術日本語

  • 2017年度   機械情報基礎

  • 2017年度   機械情報プロジェクト I

  • 2017年度   情報工学基礎実験I

  • 2017年度   電磁気学

  • 2017年度   力学

  • 2016年度   インターンシップ

  • 2016年度   情報工学基礎実験I

  • 2016年度   電磁気学

  • 2016年度   力学

  • 2016年度   機械情報基礎

  • 2016年度   機械情報プロジェクト I

  • 2016年度   情報物性特論

  • 2015年度   力学

  • 2015年度   電磁気学

  • 2015年度   情報工学基礎実験I

  • 2015年度   科学技術日本語

  • 2015年度   インターンシップ

  • 2015年度   機械情報プロジェクト I

  • 2015年度   機械情報基礎

  • 2014年度   力学

  • 2014年度   電磁気学

  • 2014年度   情報工学基礎実験I

  • 2014年度   長期インターンシップ

  • 2014年度   インターンシップ

  • 2014年度   機械情報プロジェクト I

  • 2014年度   機械情報基礎

  • 2014年度   情報物性特論

  • 2013年度   科学技術日本語

  • 2013年度   科学技術日本語

  • 2013年度   情報工学基礎実験I

  • 2013年度   電磁気学

  • 2013年度   力学

  • 2012年度   情報物性特論

  • 2012年度   機械情報プロジェクトⅠ

  • 2012年度   情報工学基礎実験Ⅰ

  • 2012年度   基礎物理学C・同演習

  • 2012年度   力学

▼全件表示

教育活動に関する受賞・指導学生の受賞など

  • 虹彩賞(英語名称:JLCS Kousai Poster Award)

    日本液晶学会  

    2020年10月20日

    宮川直人(指導学生)

  • 若葉賞(学生ポスター発表賞/英文名称:JLCS Student Poster Award)

    日本液晶学会  

    2020年10月20日

    塩見雅人(指導学生)