New Type of Nonlinear Optical Device using Charge-Density-Wave Collective Motion

利用电荷密度波集体运动的新型非线性光学器件

• 批准号: 12650039
• 负责人: KOYANO Mikio
• 金额: $ 1.92万
• 依托单位: Japan Advanced institute of Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-12650039/
• 关键词: Transition-metal dichalcogenide; Charge-density-wave; Nonlinear conduction; Quasi-particle; Screening effect; Two-dimensional electron gas; AlGaAs; GaAs単一ヘテロ構造; 2次元電子系; 電荷密度ゆらぎ; しきい電場; 分極変化; フォトリフラクティブ効果; 化学気相法; 電荷密度波の並進運動; 非線形光学定数

(i) Charge density fluctuation and density modulation in ideal 2-dimensional electron systemsResonant light scattering spectra from modulation doped n-type AlGaAs/GaAs single heterojunctions are studied experimentally and theoretically. Based on the light scattering formula due to the charge-density mechanism, the scattering intensities by coupled intersubband plasmon-LO phonon modes are analyzed by taking into account the electron-electron and electron-phonon interactions. Moreover, we carry out a self-consistent calculation of the density modulation of the 2-dimensional electron gas in a lateral surface superlattice.(ii) Charge-density-waves in transition-metal dichalcogenidesSingle crystals of quasi-two-dimensional conductor of TaS_2 have been synthesized by chemical vapor transport technique. Excess sulfur addition at the synthesis suppressed the charge-density-wave transition through a conduction carrier injection; the thermopower measurements revealed that the injected carrier is hole.(iii) Photo-irradiation effect on dynamics of charge-density-wave condensate in quasi-one-dimensional conductorsWe find a new photo-irradiation effect on the current-voltage characteristics of quasi-one-dimensional conductors TaS_3. When the TaS_3 single crystal is irradiated with a weak 488 nm emission from Ar^+ laser, the electrical current is enhanced around the threshold voltage V_t below the Peierls transition temperature T_p. The current enhancement is attributed to the increase of charge-density-wave contribution due to the screened pinning potentials by photo-excited quasi-particles in plastic creep phase of charge-density-wave motion.

(i) 理想二维电子系统中的电荷密度涨落和密度调制从实验和理论上研究了调制掺杂n型AlGaAs/GaAs单异质结的共振光散射光谱。基于电荷密度机制的光散射公式，考虑电子-电子和电子-声子相互作用，分析了耦合子带间等离子体-LO声子模式的散射强度。此外，我们还对横向表面超晶格中二维电子气的密度调制进行了自洽计算。(ii)过渡金属二硫化物中的电荷密度波采用化学气相传输技术合成了TaS_2准二维导体单晶。合成时添加过量的硫通过传导载流子注入抑制了电荷密度波跃迁； (iii)光辐照对准一维导体电荷密度波凝聚体动力学的影响我们发现了一种新的光辐照对准一维导体TaS_3电流-电压特性的影响。当 TaS_3 单晶受到 Ar^+ 激光的弱 488 nm 发射照射时，电流在 Peierls 转变温度 T_p 以下的阈值电压 V_t 附近增强。电流的增强归因于电荷密度波运动的塑性蠕变阶段中光激发准粒子屏蔽钉扎电势导致电荷密度波贡献的增加。

项目成果

T.Tagawa, S.Katayama: "A New Profile of the Modulated Two-dimensional Electron Density in Lateral Surface Superlattices"Journal of Korean Physical Society. 39(3). 481-484 (2001)

T.Takawa、S.Katayama：“横向表面超晶格中调制二维电子密度的新轮廓”韩国物理学会杂志。

T.Tagawa, S.Katayama: "Plasmons in laterally Density Modulated 2D Electron Gas in Shallow Etched Single-heterostructures"Proceeding of the 25th International Conference on the Physics of Semiconductors (Osaka, 2000). 481-482 (2001)

T.Takawa、S.Katayama：“浅蚀刻单异质结构中横向密度调制二维电子气体中的等离激元”第 25 届国际半导体物理会议论文集（大阪，2000 年）。

S. M. Maung, S. Katayama, M. Koyano and S. Yamada: "Ionic Screening Effects on Resonant Light Scattering by Intersubband Excitations in n-type AiGaAs/GaAs Heterojunctions"Proceedings of the 28th International Symposium on Compound Semiconductors (Tokyo, 2

S. M. Maung、S. Katayama、M. Koyano 和 S. Yamada：“n 型 AiGaAs/GaAs 异质结中子带间激发对共振光散射的离子屏蔽效应”第 28 届国际化合物半导体研讨会论文集（东京，2

小矢野 幹夫: "遷移金属ダイカルコゲナイドのインターカレーションと伝導物質"金属(特集 硫化物の物性と製造プロセス). 70・7. 535-542 (2000)

Mikio Oyano：“过渡金属二硫化物的插层和导电材料”金属（硫化物的物理性质和制造工艺专题）70・7（2000）。

T.Isa, T.Fukase, M.Sasaki, M.Koyano, et al.: "Mid-gap State Formed Inside Mott Gap of 1T-TaS_2 Single Crystals and Metal-Insulator Transition"Journal of Low Temperature Physics. 127(1/2). 63-79 (2002)

T.Isa、T.Fukase、M.Sasaki、M.Koyano 等人：“1T-TaS_2 单晶莫特能隙内形成的中能隙态及金属-绝缘体转变”《低温物理学杂志》。