Density dependence of spin relaxation in GaAs quantum well at room temperature
Density dependence of spin relaxation in GaAs quantum well at room temperature
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DOI：
10.1209/0295-5075/84/27006
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发表时间：
2008-06
期刊：
影响因子：
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通讯作者：
L. Teng;P. Zhang;T. Lai;M. W. Wu
中科院分区：
文献类型：
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作者：
L. Teng;P. Zhang;T. Lai;M. W. Wu
利用时间分辨圆偏振抽运探测光谱，在室温下研究了本征量子阱中电子自旋弛豫随载流子密度的变化。结果表明，在密度较低，线性D‘yakonov-Perel自旋-轨道耦合项占主导地位的情况下，自旋弛豫时间随密度增加而增加，当密度较大，立方D’yakonov-Perel自旋-轨道耦合项变得重要时，自旋弛豫时间趋于减小。这些特征与L等人关于自旋弛豫与密度相关的理论预言是一致的。(物理。修订本B，73(2006年)125314)。通过数值求解包含D‘yakonov-Perel’和Bir-Aronov-Pikus机制的动力学自旋Bloch方程的全微观计算，很好地再现了自旋弛豫的密度依赖性。
Carrier density dependence of electron spin relaxation in an intrinsic GaAs quantum well is investigated at room temperature using time-resolved circularly polarized pump-probe spectroscopy. It is revealed that the spin relaxation time first increases with density in the relatively low-density regime where the linear D'yakonov-Perel' spin-orbit coupling terms are dominant, and then tends to decrease when the density is large and the cubic D'yakonov-Perel' spin-orbit coupling terms become important. These features are in good agreement with theoretical predictions on density dependence of spin relaxation by Lüet al. (Phys. Rev. B, 73 (2006) 125314). A fully microscopic calculation based on numerically solving the kinetic spin Bloch equations with both the D'yakonov-Perel' and the Bir-Aronov-Pikus mechanisms included, reproduces the density dependence of spin relaxation very well.