Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases (2DEGs) with Rashba and Dresselhaus spin-orbit interactions (SOIs), based on the quantum field theory. We derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic (EM) field. We calculate the Casimir-Lifshitz torque (CLT) between two parallel 2DEGs with Rashba and Dresselhaus SOIs, which can be tuned by changing the relative strength between two SOIs. The anisotropic Casimir energy between 2DEGs caused by the interplay between the SOIs of 2DEGs offers a new origin of CLT and a new type of optoelectronic device.