Non-linear Optical Responses and Many-Body Effects of Excitonic Fano Resonance States

激子法诺共振态的非线性光学响应和多体效应

• 批准号: 16540279
• 负责人: HINO Ken-ichi
• 金额: $ 2.5万
• 依托单位: University of Tsukuba
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2006
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540279/
• 关键词: Semiconductor Superlattices; Wannier-Stark Ladder; Zener Effect; Floquet State; Semiconductor Bloch Equations; Non-Linear Optical Response; Many-Body Effect; Exciton; 動的Zener効果; 2次Zeeman効果; Wannier-Stark ladder; Fano共鳴; Zenerトンネリング; 動的Wannier

The present research project is aimed at the theoretical understanding of the non-linear optical response and the many-body effect on semiconductor superlattices with a static electric field along the direction of the crystal growth, termed the Wannier Stark ladder (WSL). In particular, an attention is paid to such two effects on excitonic Fano resonance (FR) states ascribable to the low dimensionality of the semiconductor concerned. The main research results are enumerated in the following :(1) Zener effects on WSL-FR states under an intense static electric fieldPhotoabsorption spectra of an exciton of this system are simulated based on the multi-channel scattering theory. The strong anticrossing between the subband energies of a carrier (an electron or a hole) and the conspicuous delocalization of the associated wavefunctions are observed under the particular applied electric field giving rise to the Zener resonance. This results in strong modulation of the exciton spectra as a funct … More ion of strength of the electric field. To put it concretely, the red shift of the absorption edge and the irregular variation of the FR profile are found.(2) Asymmetric doublet splitting of the dressed exciton FR state in the degenerate four-wave mixing (DFWM) spectroscopyBased on the semiconductor Bloch equations in view of the many-body effect, the DFWM signals of the WSL are examined, where both strong pump pulse laser and relatively weak probe pulse laser are irradiated on this target. It is known that the symmetric doublet splitting attributed to an ordinary exciton bound state is observed in the spectrally-resolved DFWM spectra, which is termed the Autler-Townes splitting. On the other hand, when the exciton FR state is particularly concerned, it is found that the spectra become asymmetric, resulting from the interference of the microscopic polarization coherence and the FR wave function with the phase reflecting the degree of the magnitude of the Fano-q value. The profile and the energy position of the novel doublet greatly depend on the many-body effect as well as the intensity of the pump light.(3) ac-Zener effect of the dynamic WSL (DWSL)The system of the WSL strongly coupled with a THz laser with periodic repetition is termed the DWSL. It is well known that the Floquet state of the DWSL can be coherently controlled by means of a monochromatic laser. Here, the ac-Zener effect on the DWSL driven by a periodic pulse train is examined by calculating the quasienergies and the absorption spectra of the associated Floquet states. The novel possibility of the quantum control is found that the ac-Zener effect of the DWSL can be coherently removed when the wave form of the pulse is of the either square or saw-toothed shape. On the other hand, as regards the periodic pulse train with other wave forms, it is found that anomalous negative absorption manifest itself with increasing the intensity of the laser concerned. Less

本研究项目旨在对非线性光学响应的​​理论理解以及对半导体超晶格的多体效应，并沿着晶体生长的方向具有静态电场，称为Wannier Stark Ladder（WSL）。特别是，人们注意这两种影响对令人兴奋的Fano共振（FR）状态可归因于相关半导体的低维度。在以下内容中列举了主要的研究结果：（1）基于多通道散射理论，模拟了该系统的激发源的强烈静态电场射击光谱，对WSL-FR状态的齐纳对WSL-FR状态的影响。在特定的施加电场下观察到载体（电子或孔）的子带能量（电子或孔）的子带能量与相关波形的明显离域之间的强抗抗肿，从而引起了Zener的共振。这会导致对刺激光谱的强烈调制，作为一种功能……更多的电场强度离子。 To put it closely, the red shift of the abstraction edge and the irregular variation of the FR profile are found.(2) Asymmetric doublet splitting of the dressed exciting FR state in the degenerate four-wave mixing (DFWM) spectroscopyBased on the semiconductor Bloch equations in view of the many-body effect, the DFWM signals of the WSL are examined, where both strong pump pulse laser and relatively weak探针脉冲激光器在该目标上被照射。众所周知，在光谱分辨的DFWM光谱中观察到归因于普通刺激状态的对称双重分裂，该光谱称为自动型镇分裂。另一方面，当特别涉及令人兴奋的FR状态时，发现光谱是由于显微镜极化相干性的干扰和FR波函数而导致的，并且具有反映Fano-Q值幅度程度的相位。新颖双线的曲线和能量位置在很大程度上取决于多体效应以及泵光的强度。（3）动态WSL（DWSL）的ac-Zener效应WSL的系统与THZ激光器的系统系统与周期性重复息息相关。众所周知，DWSL的Floquet状态可以通过单色激光连贯控制。在这里，通过计算相关浮雕状态的准耐药和抽象光谱，检查了通过定期脉冲序列对DWSL驱动器的AC型效应。发现量子对照的新型可能性是，当脉冲的波形是正方形或锯齿状形状的波形时，DWSL的辅助效应可以连贯地去除。另一方面，关于具有其他波形的周期性脉冲序列，发现异常的负滥用会随着相关激光的强度的增加而表现出来。较少的

项目成果

Removal of interminiband interactions in dynamic Wannier-Stark ladder by means of a pulse train with periodic repetition

通过周期性重复的脉冲序列消除动态 Wannier-Stark 阶梯中的小带间相互作用

• 发表时间: 2006
• 期刊: Solid State Communications 138
• 作者: K.Hino;N.Toshima
• 通讯作者: N.Toshima

Interacting dynamic Wannier-Stark ladder driven by a periodic pulse train

由周期性脉冲串驱动的交互动态 Wannier-Stark 梯子

• 发表时间: 2008
• 期刊: Physical Review B 77
• 作者: K. Hino;X. M. Tong and N. Toshima
• 通讯作者: X. M. Tong and N. Toshima

Phase dependent atomic ionization in few-cycle laser fields : direct ionization and rescattering

少周期激光场中的相位相关原子电离：直接电离和再散射

• 发表时间: 2006
• 期刊: Phys. Rev. A 74
• 作者: X.M.Tong;K.Hino;N.Toshima
• 通讯作者: N.Toshima

Dimensionality transitions of exciton Fano-resonance spectra in a semiconductor Wannier-Stark ladder

半导体 Wannier-Stark 梯中激子 Fano 共振光谱的维数跃迁

• 发表时间: 2005
• 期刊: Solid State Communications 135
• 作者: K.Hino;N.Toshima
• 通讯作者: N.Toshima

Spectral modulation of exciton Fano resonance due to Zener breakdown in strongly biased superlattices

强偏置超晶格中齐纳击穿引起的激子法诺共振的光谱调制

• 发表时间: 2005
• 期刊: Phys. Rev. B 71
• 作者: K.Hino;N.Toshima
• 通讯作者: N.Toshima