AI 中文总结
研究二维电子气中非磁性点杂质周围光致直流电流态和磁场，基于含时薛定谔方程二阶微扰解发现逆法拉第效应情形与标准不同，预测的整流电流机制具普遍性，内部直流磁场可引发光致霍尔效应和法拉第旋转。
AI 中文摘要
我们对二维电子气中，非磁性点杂质周围受圆偏振电磁波辐照时的光致直流电流态和磁场进行了量子力学描述。基于在电磁波振幅二阶微扰理论下相应含时薛定谔方程的解，我们发现二维系统平面垂直方向上产生的直流磁场分量，分布如同一组与杂质位置绑定的随机磁通量。因此，远离样品边缘时空间平均直流磁场并不消失，所以我们在无序系统中逆法拉第效应的情形，与基于流体动力学或动力学方程方法中弛豫时间近似的标准情形有很大不同，后者仅给出沿样品边缘流动的光致电流。所预测的围绕杂质中心形成整流电流的机制，对二维和三维系统均具有普遍性。内部直流磁场可引发探测电磁信号的光致霍尔效应和法拉第旋转。
英文摘要
We provide a quantum-mechanical description of the photoinduced dc current states and magnetic fields around nonmagnetic point impurities in a two-dimensional (2D) electron gas irradiated by a circularly polarized electromagnetic wave. Based on the solution of the corresponding time-dependent Schrodinger equation within the second-order perturbation theory in the electromagnetic wave amplitude we find that the resulting dc magnetic field component perpendicular to the plane of the 2D system is distributed like in a set of random magnetic fluxes bound to the positions of impurities. As a result, the spatially averaged dc magnetic field does not vanish far from the sample edges and, thus, our scenario of the inverse Faraday effect in disordered systems differs strongly from the standard one based on the relaxation time approximation within the hydrodynamic or kinetic equation approaches which would give only the photoinduced currents flowing along the sample edges. The predicted mechanism for formation of rectified currents flowing around the impurity centers is shown to be generic both for 2D and three-dimensional systems. The internal dc magnetic field can give rise to the photoinduced Hall effect and Faraday rotation for a probing electromagnetic signal.
Comments15 pages, 3 figures
