title: Spin transport in undoped InGaAs/AlGaAs multiple quantum well studied via spin photocurrent excited by circularly polarized light.
abstract: The spin diffusion and drift at different excitation wavelengths and different temperatures have been studied in undoped InGaAs/AlGaAs multiple quantum well (MQW). The spin polarization was created by optical spin orientation using circularly polarized light, and the reciprocal spin Hall effect was employed to measure the spin polarization current. We measured the ratio of the spin diffusion coefficient to the mobility of spin-polarized carriers. From the wavelength dependence of the ratio, we found that the spin diffusion and drift of holes became as important as electrons in this undoped MQW, and the ratio for light holes was much smaller than that for heavy holes at room temperature. From the temperature dependence of the ratio, the correction factors for the common Einstein relationship for spin-polarized electrons and heavy holes were firstly obtained to be 93 and 286, respectively.
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. lpzhu@semi.ac.cn.|Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, National Center for Nanoscience and Technology (NCNST), Beijing, 100083, People's Republic of China. lpzhu@semi.ac.cn.
authors.forename: Laipan
authors.identifier: http://orcid.org/0000-0002-5135-4357
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. liuyu@semi.ac.cn.
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. whuang@semi.ac.cn.
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. qinxd@semi.ac.cn.
authors.forename: Xudong
authors.initials: X
authors.lastname: Qin
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. liyuan12@semi.ac.cn.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. wuqing@semi.ac.cn.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, People's Republic of China. yhchen@semi.ac.cn.
authors.forename: Yonghai
authors.initials: Y
authors.lastname: Chen
keywords: Spin diffusion; Spin drift; The circularly polarized light; The reciprocal spin Hall effect