Coherent Propagation and Many-Body Effects of Exciton Masses at Semiconductor Interfaces

半导体界面处激子质量的相干传播和多体效应

• 批准号: 11215208
• 负责人: KARASAWA Tsutomu
• 金额: $ 32.77万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas (B)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11215208/
• 关键词: high-density excitons; BiI_3 staccking fault exciotns; layered crystals (GaSe, PbI_2); exciton superfluidity; GaAs; AlAs super lattices; type-II super lattice and quantum wells; Bose-Einstein statistics; macroscopic quantum phenomena on excitons /

In our research, photoinduced high-density effects on excitons and phonons, and their coherent propagation at quasi tow-dimensional interfaces in semiconductors have been studied from experimental and theoretical aspects.In layered crystals BiI_3, GaSe, and PbI_2, we have studied spatial and temporal behavior of high-density exciton masses and their nonlinear optical responses. In BiI_3, extraordinarily large spatial expansion of the excitons confined in a tow-dimensional stacking fault interface (SFE) was observed in the space- and time-resolved photoluminescence above a threshold excitation density. The degenerate four-wave-mixing (DFWM) light induced by spatially isolated two laser-light spots tuned to the SFE state on the sample surface was emitted owing to the coherent transport of the exciton mass from one to the other exciting spot sites showing the SFE-polariton masses being in a Bose-condensed phase. In GaSe as well as PbI_2, it turned out that heavy photo-excitation brings ab … More out recoil luminescence due to scattering with the other excitons or carriers in competition with the biexciton formation.For the excitonic properties and coherent-phonon phenomena in superlattices (SLs), we have obtained the following results. (1) In GaAs/AlAs type-II SLs, where the electron and hole are spatially separated in the AlAs and GaAs layers respectively, the density relation of the excition-biexciton system in the decay process is dominated by Bose-Einstein statistics, which results in a threshold-like increase in the biexciton density. (2) In GaAs/AlAs type-I SLs, the transformation process from the biexciton to the electron-hole-plasma phase is revealed, connecting with the band-gap renormalization due to high-density carriers. (3) In InAs/GaAs SLs, the photoexcited plasmon couples with the GaAs-like coherent-LO phonon through the miniband state.We have theoretically studied macroscopic quantum phenomena in an interacting dilute quasi-two-dimensional Bose gas of excitons in a type-II semiconductor quantum wells and clarified its ordered states, elementary excitations and mechaisms of phase transitions. Less

本论文从实验和理论两方面研究了半导体中激子和声子的光致高密度效应及其在准二维界面上的相干传输，在BiI_3、GaSe和PbI_2层状晶体中研究了高密度激子质量的时空行为及其非线性光学响应。在BiI_3中，在高于阈值激发密度的时空分辨光致发光中，观察到二维堆垛层错界面（SFE）中激子的极大空间膨胀.由于激子质量从一个激发点相干输运到另一个激发点，样品表面上两个调谐到SFE态的激光光斑产生简并四波混频（DFWM）光，表明SFE极化激元质量处于玻色凝聚相。在GaSe和PbI_2中，强光激发引起了 ...更多信息 超晶格中的激子性质和相干声子现象，我们得到了以下结果：（1）超晶格中的激子性质和相干声子现象。(1)在GaAs/AlAs Ⅱ型超晶格中，电子和空穴分别在AlAs和GaAs层中空间分离，激发-双激子系统在衰减过程中的密度关系受玻色-爱因斯坦统计支配，导致双激子密度呈阈值状增加. (2)在GaAs/AlAs第I类超晶格中，揭示了从双激子到电子-空穴-等离子体相的转变过程，并与高密度载流子引起的带隙重整化有关。(3)在InAs/GaAs超晶格中，光激发等离子体激元通过迷你带态与类GaAs相干LO声子耦合，我们从理论上研究了II型半导体量子威尔斯中激子相互作用的准二维玻色气体中的宏观量子现象，阐明了其有序态、元激发和相变机制。少

项目成果

H.Takeuchi, K.Mizoguchi, M.Nakayama: "Coherent phonon-plasmon coupled modes in(InAs)_l/(GaAs)_m strained-layer superlattices"Proceedings of the 10th International Conference on Narrow Gap Semiconductors and Related Small Energy Phenomena,IPAP Conf.. Serie

H.Takeuchi、K.Mizoguchi、M.Nakayama：“(InAs)_l/(GaAs)_m 应变层超晶格中的相干声子-等离子体耦合模式”第十届窄带隙半导体及相关小能量现象国际会议论文集，

M.Shin'i, M.Suzuki: "Hierarchic natures and dynamics of photoinduced structural phase transition in non-degenerate charge density wave states via successive photoexcitations"Phase Transitions. (印刷中). (2002)

M.Shini，M.Suzuki：“通过连续光激发的非简并电荷密度波状态的光致结构相变的层次性质和动力学”（出版中）。

H. Mino, M. Yamamoto, T. Kawai, I. Akai, T. Karasawa: "Anomalose Behavior of the High-Density Excitons and their Nonlinear Optical Response in a Quasi Two-Dimensional Space in a Layered Crystal Bil_3"J. Lumin.. (印刷中).

H. Mino、M. Yamamoto、T. Kawai、I. Akai、T. Karasawa：“层状晶体 Bil_3 中准二维空间中高密度激子的反常行为及其非线性光学响应”J。 ..（印刷中）。

三野弘文、山本勝哉、河相武利、赤井一郎、唐沢 力: "層状結晶BiI_3 中高密度励起子のコヒーレント伝播と光誘起空間凝縮相"第10回光物性研究会 論文集. 253-256 (1999)

Hirofumi Mino、Katsuya Yamamoto、Taketoshi Kawasai、Ichiro Akai、Chikara Karasawa：“层状晶体 BiI_3 中中高密度激子的相干传播和光致空间凝聚相”第 10 届光物理物理研究组论文集 253-256（1999 年）。 ）

市田秀樹、中山正昭: "GaAs/AlAsタイプ-II超格子におけるタイプ電子・正孔プラズマ"第10回光物性研究会 論文集. 245-248 (1999)

Hideki Ichida、Masaaki Nakayama：“GaAs/AlAs II 型超晶格中的电子空穴等离子体”第 10 届光物理物理研究组论文集 245-248 (1999)。