外磁场对(Ga,Mn)As有效g因子的影响  

Effects of external magnetic field on the effective g factor of (Ga,Mn) As

作　　者：周蓉[1] 孙宝权[1] 阮学忠[1] 甘华东[1] 姬扬[1] 王玮竹[1] 赵建华[1] 

机构地区：[1]中国科学院半导体研究所超晶格与微结构国家重点实验室,北京100083

出　　处：《物理学报》2008年第8期5244-5248,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10334030;60676054)资助的课题~~

摘　　要：利用时间分辨Kerr旋光技术测量低温下稀磁半导体Ga0.937Mn0.063As中光注入极化载流子的自旋进动信号,并观察到自旋极化载流子的有效g因子值随外磁场的增强而增大的反常现象.这归结于磁场导致局域化空穴转化为非局域化空穴,从而使自发磁化强度增强,有效g因子值增大.基于此物理图像,进一步给出了(Ga,Mn)As的有效g因子与外磁场的关系式.With the help of time resolved magneto-optic Kerr rotation measurements,the optically induced spin precession in heavily doped diluted magnetic semiconductor Ga0.937Mn0.063As was observed.It was found that the effective g factor increases with increasing magnetic field,which is attributed to the magnetic-field-induced increase of the density of the non-localized holes.Those free holes will couple with the localized magnetic ions by p-d interactions,leading to the formation of spontaneous magnetization in Ga0.937Mn0.063As,which in turn to the enhancement of the effective g factor.

关 键 词：时间分辨Kerr旋光测量 ZEEMAN效应 Ruderman-Kittel-Kasuya-Yosida模型 

分 类 号：O472[理学—半导体物理]