Department of Physics, Indian Institute of Technology-Kanpur, Kanpur-208 016, India.
J Phys Condens Matter. 2012 May 9;24(18):185303. doi: 10.1088/0953-8984/24/18/185303. Epub 2012 Apr 5.
We study the electrical transport properties of a two-dimensional electron gas (2DEG) with the Rashba spin-orbit interaction in the presence of a constant perpendicular magnetic field (B(0)( ̂z) which is weakly modulated by B1 = B1 cos(qx) ̂z, where B(1) ≪ B(0) and q = 2π/a with a the modulation period. We obtain the analytical expressions of the diffusive conductivities for spin-up and spin-down electrons. The conductivities for spin-up and spin-down electrons oscillate with different frequencies and produce beating patterns in the amplitude of the Weiss and Shubnikov-de Haas oscillations. We show that the Rashba strength can be determined by analyzing the beating pattern in the Weiss oscillation. We find a simple equation which determines the Rashba spin-orbit interaction strength if the number of Weiss oscillations between any two successive nodes is known from the experiment. We compare our results with the electrically modulated 2DEG with the Rashba interaction. For completeness, we also study the beating pattern formation in the collisional and the Hall conductivities.
我们研究了在存在外加弱调制磁场 B1 = B1 cos(qx) ̂z（其中 B(1) ≪ B(0) 且 q = 2π/a，a 为调制周期）的二维电子气（2DEG）中， Rashba 自旋轨道相互作用的电输运性质。我们得到了自旋向上和自旋向下电子的扩散电导率的解析表达式。自旋向上和自旋向下电子的电导率以不同的频率振荡，并在 Weiss 和 Shubnikov-de Haas 振荡的幅度中产生拍频图案。我们表明，通过分析 Weiss 振荡中的拍频图案，可以确定 Rashba 强度。如果从实验中已知任意两个连续节点之间的 Weiss 振荡的数量，则我们找到了一个简单的方程来确定 Rashba 自旋轨道相互作用强度。我们将我们的结果与具有 Rashba 相互作用的电调制 2DEG 进行了比较。为了完整性，我们还研究了碰撞和 Hall 电导率中的拍频图案形成。
