Decoherence-assisted initialization of a resident hole spin polarization in a p-doped semiconductor quantum well
Decoherence-assisted initialization of a resident hole spin polarization in a p-doped semiconductor quantum well
复制标题
p 掺杂半导体量子阱中驻留空穴自旋极化的退相干辅助初始化
DOI：
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
T. Korn
中科院分区：
文献类型：
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作者：
M. Kugler;K. Korzekwa;P. Machnikowski;C. Gradl;S. Furthmeier;M. Griesbeck;M. Hirmer;D. Schuh;W. Wegscheider;T. Kuhn;C. Schuller;T. Korn
我们研究了p调制掺杂的GaAsAl0.3Ga0.7As单量子阱中驻留空穴的自旋动力学。在我们的研究中使用了时间分辨的法拉第和克尔旋转，以及共振自旋放大。我们观察到，非共振或高功率光泵浦导致相对于光取向载流子符号相反的驻留空穴自旋极化，而低功率共振光泵浦只在施加足够的面内磁场时才导致驻留空穴自旋极化。自旋取向的两个不同过程之间的竞争强烈地改变了共振自旋放大迹的形状。对电子-空穴系统中自旋动力学的计算与实验中的Kerr旋转和共振自旋放大轨迹很好地吻合，并使我们能够确定样品在光学取向后的空穴自旋极化，以及提取关于演化不同阶段的自旋退相过程的定量信息。
We investigate spin dynamics of resident holes in a p-modulation-doped GaAs/Al0.3Ga0.7As single quantum well. Time-resolved Faraday and Kerr rotation, as well as resonant spin amplification, are utilized in our study. We observe that nonresonant or high-power optical pumping leads to a resident hole spin polarization with opposite sign with respect to the optically oriented carriers, while low-power resonant optical pumping only leads to a resident hole spin polarization if a sufficient in-plane magnetic field is applied. The competition between two different processes of spin orientation strongly modifies the shape of resonant spin amplification traces. Calculations of the spin dynamics in the electron-hole system are in good agreement with the experimental Kerr rotation and resonant spin amplification traces and allow us to determine the hole spin polarization within the sample after optical orientation, as well as to extract quantitative information about spin dephasing processes at various stages of the evolution.