Anisotropic spin diffusion in a semiconductor quantum well
V. N. Gridnev
A. F. Ioffe Physico-Technical Institute RAS, 194021 St. Petersburg, Russia
PACS: 71.70.Ej, 75.40.Gb, 78.47.+p
Abstract
We show that spin diffusion of an inhomogeneous spin density
distribution in an asymmetric zinc-blende semiconductor quantum well is
anisotropic in coordinate space, if the D'yakonov-Perel' spin relaxation
mechanism is dominant. This anisotropy depends on the relation between the
Dresselhaus and Rashba contributions to the spin splitting and reaches its
maximum when the both contributions are equal in magnitude. Under this
condition the temporal behavior of the spin density strongly depends on the
relation between the initial spatial extent of the spin packet and spin
diffusion length.