Abstract
We derive a spin diffusion equation for a spin-orbit coupled two-dimensional electron gas including the Hartree-Fock field resulting from first order electron-electron interactions. We find that the lifetime of the persistent spin helix, which emerges for equal linear Rashba and Dresselhaus spin-orbit interactions, can be enhanced considerably for large initial spin polarizations due to the Hartree-Fock field. The reason is a reduction of the symmetry-breaking cubic Dresselhaus scattering rate by the Hartree-Fock field. Also higher harmonics are generated and the polarization of the persistent spin helix rotates out of the (,) plane acquiring a finite component. This effect becomes more pronounced when the cubic Dresselhaus spin-orbit interaction is large.
- Received 11 January 2013
DOI:https://doi.org/10.1103/PhysRevB.87.125416
©2013 American Physical Society