Diffusion of inhomogeneous spin distribution in a magnetic field parallel to interfaces of a III-V semiconductor quantum well

Abstract

We have studied the diffusive relaxation of inhomogeneous electron-spin polarization, induced by a delta-function source in a III-V semiconductor quantum well under a weak magnetic field applied parallel to the interfaces. We have found that, due to the interplay between the magnetic field and the spin-orbit interaction, the evolution behavior of a spin packet is qualitatively different from the well-known exponential relaxation with the D'yakonov-Perel relaxation rate. It is shown that during the propogation the shape of a spin-packet displays oscillations in space and time, and the amplitude of the oscillations depends on the direction and the strength of the magnetic field.