作　　者： ; ; ; ; ; ;

机构地区： 中山大学

出　　处： 《物理学报》 2009年第5期3543-3547,共5页

摘　　要： 发展了一种时-空分辨圆偏振光抽运-探测光谱及其理论,并用于本征GaAs量子阱中电子自旋扩散输运的实验研究.获得室温下本征GaAs量子阱中的"自旋双极扩散系数"为Das=37.5±15cm2/s.此结果比用自旋光栅法测量到的掺杂GaAs量子阱中电子自旋扩散系数小.解释为是由于"空穴库仑拖曳"效应减慢了电子自旋波包的扩散输运. A time- and space-resolved circularly polarized pump-probe spectroscopy and its theory are developed, and are used experimentally to study electron spin diffusion transport in intrinsic GaAs quantum wells. The ambipolar spin diffusion coefficient of Das = 37.5 ＋ 15 cm^2/s is obtained at room temperature, and is smaller than that in a doped GaAs quantum well obtained by spin grating. The difference is explained based on ＂hole Coulomb drag＂ effect which slows the diffusion transport of electron spin packet.

关 键 词： 时 空分辨抽运 探测光谱 电子自旋扩散 量子阱

领　　域： [理学] [理学] [电子电信]