Temperature and electron density dependence of spin relaxation in GaAs/AlGaAs quantum well.
Temperature and electron density dependence of spin relaxation in GaAs/AlGaAs quantum well.
复制标题
GaAs/AlGaAs 量子阱中自旋弛豫的温度和电子密度依赖性
DOI：
10.1186/1556-276x-6-84
复制
发表时间：
2011-01-12
影响因子：
--
通讯作者：
Niu Z
中科院分区：
文献类型：
--
作者：
Han L;Zhu Y;Zhang X;Tan P;Ni H;Niu Z
利用时间分辨克尔旋转技术研究了具有不同结构对称性的GaAs/AlGaAs量子威尔斯（QW）的自旋动力学随温度和载流子密度的变化。自旋弛豫时间的测量结果表明，对称量子阱的自旋弛豫时间比非对称量子阱的自旋弛豫时间要长得多，表明Rashba自旋轨道耦合对自旋弛豫有很强的影响. D 'yakonov-Perel'机制是GaAs/AlGaAs量子阱自旋弛豫的主要机制。自旋弛豫时间表现出非单调依赖于温度和光激发载流子密度的行为，揭示了电子-电子库仑散射的非单调温度和密度依赖性的重要作用。我们的实验观察表明，与最近发展的自旋弛豫理论的基础上微观动力学自旋布洛赫方程的方法很好的协议。
Temperature and carrier density-dependent spin dynamics for GaAs/AlGaAs quantum wells (QWs) with different structural symmetries have been studied by using time-resolved Kerr rotation technique. The spin relaxation time is measured to be much longer for the symmetrically designed GaAs QW comparing with the asymmetrical one, indicating the strong influence of Rashba spin-orbit coupling on spin relaxation. D'yakonov-Perel' mechanism has been revealed to be the dominant contribution for spin relaxation in GaAs/AlGaAs QWs. The spin relaxation time exhibits non-monotonic-dependent behavior on both temperature and photo-excited carrier density, revealing the important role of non-monotonic temperature and density dependence of electron-electron Coulomb scattering. Our experimental observations demonstrate good agreement with recently developed spin relaxation theory based on microscopic kinetic spin Bloch equation approach.