论文标题
无序系统中旋转动力学的半经典理论
The semiclassical theory for spin dynamics in a disordered system
论文作者
论文摘要
我们研究了二维自旋轨道耦合系统中自旋动力学的灌溉模型。在没有施加的电场的情况下，自旋与K依赖性有效磁场对齐。考虑了疾病（动量放松时间$τ$）对系统的影响。在存在电场的情况下，动量的变化会导致有效磁场的变化。平面自旋可以在有效磁场方向的连续变化围绕。我们发现，直到电场的线性顺序，旋转方向都经历了像拉莫般的和非武器一样的动力。此外，我们发现在很短的时间内（$ t \llτ$）的非劳动运动完全等于从库博公式获得的结果。这意味着Kubo公式仅在很短的演化中捕获系统的响应。通过分析计算RASHBA系统中LARMOR和非部位进动的自旋大机电导率。我们发现，当rashba旋转轨道耦合降至零时，固有的自旋 - 旋转电流不是通用常数，并且正确降至零。我们还计算了K-Acubic Rashba系统的时间平均Larmor和非劳动自旋式霍尔电导率（SHC），并将其与实验值进行比较。 Wunderlich等人的时间平均larmor SHC消失了，而非劳动SHC的$ 2.1（q/8π）$给出了$ 2.1（q/8π）$，非常接近实验值$ 2.2（q/8π）$。 [物理。莱特牧师。 {\ bf 94}，047204（2005）]。
We investigate the Drude model of spin dynamics in two-dimensional spin-orbit coupled systems. In the absence of an applied electric field, the spin aligns with the k-dependent effective magnetic field. The influence of disorder (the momentum relaxation time $τ$) on the system is considered. In the presence of an electric field, the change in momentum causes a change in the effective magnetic field. The in-plane spin can precess around the successive change in the orientation of the effective magnetic field. We find that up to the linear order of the electric field, the spin orientation undergoes Larmor-like and non-Larmor like precession. Furthermore, we find that the non-Larmor motion over a very short time ($t\llτ$) exactly equals the result obtained from the Kubo formula. This means that the Kubo formula only captures the system's response over a very short evolution. The spin-Hall conductivity for Larmor and non-Larmor precession in the Rashba system is analytically calculated. We find that the intrinsic spin-Hall current is not a universal constant and correctly drops to zero when the Rashba spin-orbit coupling drops to zero. We also calculate the time-averaged Larmor and non-Larmor spin-Hall conductivities (SHCs) for the k-cubic Rashba system and compare them to experimental values. The time-averaged Larmor SHC vanishes and the non-Larmor SHC is given by $2.1(q/8π)$ which is very close to the experimental value $2.2(q/8π)$ by Wunderlich et al. [Phys. Rev. Lett. {\bf 94}, 047204 (2005)].
