Current-induced spin polarization in anisotropic spin-orbit fields.

The magnitude and direction of current-induced spin polarization and spin-orbit splitting are measured in In0.04Ga0.96 As epilayers as a function of in-plane electric and magnetic fields. We show that, contrary to expectation, the magnitude of the current-induced spin polarization is smaller for crystal directions corresponding to larger spin-orbit fields. Furthermore, we find that the steady-state in-plane spin polarization does not align along the spin-orbit field, an effect due to anisotropy in the spin relaxation rate.