论文标题
在GAAS/ALGAAS量子井中的二维电子气体中自旋松弛的异常磁抑制
Anomalous magnetic suppression of spin relaxation in a two-dimensional electron gas in a GaAs/AlGaAs quantum well
论文作者
论文摘要
我们研究了限制在GAAS/ALGAAS量子孔中的二维电子气体中的自旋动力学。发现了自旋松弛的异常磁场依赖性：随着磁场变得更强大，自旋松弛时间首先增加，但随后变化为线性依赖性，然后最终变为振荡，从而分别在纵向和横向时间达到最大值，并分别在偶数上达到最大值。我们表明，自旋弛豫的抑制是由于电子循环对自旋轨道场的影响，而振荡对应于在低温和高磁场下出现状态密度的振荡。从二次依赖性到线性依赖性的过渡可能与从经典到BOHM扩散的过渡有关，并且反映了与磁化等离子体中观察到的二维电子气体的异常行为。
We study the spin dynamics in a high-mobility two-dimensional electron gas confined in a GaAs/AlGaAs quantum well. An unusual magnetic field dependence of the spin relaxation is found: as the magnetic field becomes stronger, the spin relaxation time first increases quadratically but then changes to a linear dependence, before it eventually becomes oscillatory, whereby the longitudinal and transverse times reach maximal values at even and odd filling Landau level factors, respectively. We show that the suppression of spin relaxation is due to the effect of electron gyration on the spin-orbit field, while the oscillations correspond to oscillations of the density of states appearing at low temperatures and high magnetic fields. The transition from quadratic to linear dependence can be related to a transition from classical to Bohm diffusion and reflects an anomalous behavior of the two-dimensional electron gas analogous to that observed in magnetized plasmas.
