Determining the sign of g factor via time-resolved Kerr rotation spectroscopy with a rotatable magnetic field  

作　　者：谷晓芳 钱轩 姬扬 陈林 赵建华 

机构地区：[1]State Key Laboratory for Superlattices and Microstructures,Institute of Semiconductors,Chinese Academy of Sciences

出　　处：《Chinese Physics B》2011年第8期415-418,共4页中国物理B（英文版）

基　　金：Project supported by the National Basic Research Program of China (Grant No. 2009CB929301);the National Natural Science Foundation of China (Grant No. 10911130232)

摘　　要：Time-resolved Kerr rotation spectroscopy is used to determine the sign of the g factor of carriers in a semiconductor material, with the help of a rotatable magnetic field in the plane of the sample. The spin precession signal of carriers at a fixed time delay is measured as a function of the orientation of the magnetic field with a fixed strength B. The signal has a sine-like form and its phase determines the sign of the g factor of carriers. As a natural extension of previous methods to measure the （time-resolved） photoluminescence or time-resolved Kerr rotation signal as a function of the magnetic field strength with a fixed orientation, such a method gives the correct sign of the g factor of electrons in GaAs. Furthermore, the sign of carriers in a （Ga, Mn）As magnetic semiconductor is also found to be negative.Time-resolved Kerr rotation spectroscopy is used to determine the sign of the g factor of carriers in a semiconductor material, with the help of a rotatable magnetic field in the plane of the sample. The spin precession signal of carriers at a fixed time delay is measured as a function of the orientation of the magnetic field with a fixed strength B. The signal has a sine-like form and its phase determines the sign of the g factor of carriers. As a natural extension of previous methods to measure the （time-resolved） photoluminescence or time-resolved Kerr rotation signal as a function of the magnetic field strength with a fixed orientation, such a method gives the correct sign of the g factor of electrons in GaAs. Furthermore, the sign of carriers in a （Ga, Mn）As magnetic semiconductor is also found to be negative.

关 键 词：g factor time-resolved Kerr rotation gallium arsenide rotatable magnetic field 

分 类 号：O469[理学—凝聚态物理]