Study of high density excitation magneto-optical phenomena in semiconductor nano-structures

系统地研究了在硫化锌或硫化镉/硫化锌第二类量子阱中，带边的高效率光致发光。我们在稀磁半导体量子阱中进行了四波混频测量，从而观察到激子-双激子量子节拍。无键双激子已知随着磁场的增加其振子强度增加，导致明显的量子拍频。时间分辨光致发光测量揭示了自旋散射对于系统中激子和双激子的非平衡动力学统计的重要性。研究发现，稀磁半导体势垒中的离子内光激发引起量子阱中激子的带电跃迁。在n掺杂稀磁半导体中，量子阱，暗的和亮的三重态cha…在强磁场作用下，更多的RRED激子光致发光跃迁被阐明。我们已经了解了在稀磁半导体中实现激子磁极化子的动力学过程和光学性质。通过与理论的比较，阐明了自旋交换相互作用引起的自陷型局域化。将飞秒泵浦和探测法拉第旋转法拉第旋转法拉第旋转应用于同一系统，证实了光致磁序。磁极化子的形成过程也被理解为与自旋动力学的关系。“重整化”效应在自旋相关激子相互作用中起着重要作用。理论上指出，激子-激子相互作用很大程度上取决于光子极化和磁场的相对方向。对有望实现高密度激发态的光子晶体进行了理论分析。由高速电子通过由晶体组成的介质球所产生的半超细胞辐射的光谱轮廓。较少

In ZnSe or CdS/ZnSe type II quantum wells, high efficiency photoluminescence at the band-edge has been investigated systematically. Charged excitons and/or their high density states have been suggested as a possible origin for the strong luminescence., We have performed four-wave-mixing measurements in dilute magnetic semiconductor quantum wells, .which leads to observation of exciton-biexciton quantum beats. An anibonding biexciton has known to increase its oscillator strength on increasing magnetic field, resulted in a pronounced quantum beat. Time-resolved photoluminescence measurements revealed the importance of spin scattering by Mn localized spins for the non-equilibrium dynamical statistics of an exciton and a biexciton in the system. It has been found that a charged exciton transition in a quantum well, is induced by Mn intra-ionic photo-excitation in the dilute magnetic semiconductor barriers. In n-doped dilute magnetic semiconductor, quantum wells, dark and bright triplet cha … More rged exciton photoluminescence transitions have been clarified subjected to a strong magnetic field. Dynamical processes and optical properties of the exciton magnetic polarons .realized in bulk-dilute magnetic semiconductors have been understood. Self-trap type localization ,induced by; a spin exchange interaction has been elucidated in comparison to the theory. Femto-second pump-and-probe Faraday rotation has been applied to the same system, and photo-induced magnetic order has been confirmed. Magnetic polaron formation process has also been understood in relationship to the spin dynamics. The "renormalization" effect plays an important role in the spin dependent exciton interaction. It has been pointed out theoretically that the exciton-exciton interaction depends much on the relative direction of photon polarization and, a rnagnetic field. Theoretical analysis has been applied to a photonic crystal, which is a candidate for realizing a high-density excitation state. Spectral profile of the semi-super cell radiation resulted from a high-speed electron passing through dielectric spheres consisting of the crystal. Less