Imaging Spin Flows in Semiconductors Subject to Electric, Magnetic, and Strain Fields

by S. A. Crooker & D. L. Smith Physical Review Letters, 15 Jun 2005 Using scanning Kerr microscopy, we directly acquire two-dimensional images of spin-polarized electrons flowing laterally in bulk epilayers of n:GaAs. Optical injection provides a local dc source of polarized electrons, whose subsequent drift and/or diffusion is controlled with electric, magnetic, and -- in particular -- strain fields. Spin precession induced by controlled uniaxial stress along the <110> axes demonstrates the direct k-linear spin-orbit coupling of electron spin to the shear (off diagonal) components of the strain tensor. Read the article