Spin Torque in Semiconductor Single Planar Tunnel Junctions

Transport in a single planar tunnel junction with electrodes made of a ferromagnetic semiconductor is analyzed theoretically in the zero- -temperature limit. Tunneling current and both (in-plane and out-of-plane) components of the spin torque exerted on one of the ferromagnetic electrodes are determined as a function of the angle\thet a between magnetic moments of the electrodes. The influence of the bias voltage and spin splitting of the electron band (in both electrodes) on the spin torque components is analyzed numerically.