自旋密度光栅和本征GaAs量子阱中的电子自旋双极扩散（英文）  

Spin concentration grating and electron spin ambipolar diffusion in intrinsic GaAs multiple quantum wells

作　　者：余华梁[1] 陈曦矅 狄俊安[1] 

机构地区：[1]闽江学院物理与电子信息工程系,福建福州350108 [2]福建师范大学物理系,福建福州350108

出　　处：《中国光学》2013年第5期710-716,共7页Chinese Optics

基　　金：Specialized Scientific Research Fundation of Higher Education Institution of Fujian Province,China(No.JK2011039);Natural Science Foundation of Fujian Province of China(No.2012D110)

摘　　要：为研究空穴对自旋极化电子扩散的影响,提出用自旋密度光栅方法来观察电子自旋扩散过程。由飞秒激光在本征GaAs多量子阱中激发产生瞬态自旋光栅和瞬态自旋密度光栅,并用于研究电子自旋扩散和电子自旋双极扩散。实验测得自旋双极扩散系数D as=25.4 cm2/s,低于自旋扩散系数D s=113.0 cm2/s,表明自旋密度光栅中电子自旋扩散受到空穴的显著影响。In order to research the effect of holes on the spin electron diffusion , a method of resonant spin am-plication called＂Spin Concentration Grating（SCG）＂ is adopt to observe the process of electron spin diffusion . Transient spin grating and spin concentration grating excited by femtosecond laser beams are used to investigate electron spin diffusion and ＂electron spin ambipolar diffusion＂ in intrinsic GaAs multiple quantum wells .The measured coefficient of ＂electron spin ambipolar diffusion＂ Das =25.4 cm 2· s-1 is lower than that of electron spin diffusion Ds=113.0 cm 2· s-1 , which indicates that the influence of holes on electron spin diffusion in spin concentration grating is notable .

关 键 词：自旋密度光栅 GAAS量子阱 电子自旋双极扩散 飞秒激光 

分 类 号：O473[理学—半导体物理]