Photomagnetic effect caused by the spin–orbit interaction in a 2D system

The 2D Rashba plane subjected to in-plane magnetic field and normal external alternating electric field is considered. The presence of magnetic field breaks in-plane symmetry of the system. It is shown that the variation of the Rashba spin–orbit constant by alternating field causes transitions between subbands with different helicities. The difference of velocities in subbands results in the stationary in-plane current perpendicular to the magnetic field. The stationary current is studied for scattering by short- and long-range impurities. If the field contains two frequencies Ω±Δ/2, the current response on difference frequency Δ appears. This current is found in the collisionless limit at Δ≪Ω.