Quantum Transport Theory of Direct Current Conductivity in the Presence of Spin-Orbit Interaction

Utilizing the conductivity formula derived using the projection-reduction method, which combines a Kang-Choi (KC) reduction identity and a state-dependent projection operator in the linear response scheme, we investigate the effect of Rashba spin-orbit coupling on the direct current (dc) conductivity of a two-dimensional electron-phonon system when the perpendicular magnetic field is applied. A diagram representation of the formula is introduced, by which the validity of the theory is confirmed. We find that the dc conductivity oscillates with the inverse magnetic fields and the peak points of the oscillation appear near the reversion points of energy branches. (C) 2012 The Japan Society of Applied Physics