Random walk approach to spin dynamics in a two-dimensional electron gas with spin-orbit coupling
Abstract
We introduce and solve a semiclassical random walk (RW) model that describes the dynamics of spin polarization waves in zinc-blende semiconductor quantum wells. We derive the dispersion relations for these waves, including the Rashba, linear and cubic Dresselhaus spin-orbit interactions, as well as the effects of an electric field applied parallel to the spin polarization wave vector. In agreement with calculations based on quantum kinetic theory [P. Kleinert and V. V. Bryksin, Phys. Rev. B 76, 205326 (2007)10.1103/PhysRevB.76.205326], the RW approach predicts that spin waves acquire a phase velocity in the presence of the field that crosses zero at a nonzero wave vector, q0 . In addition, we show that the spin-wave decay rate is independent of field at q0 but increases as (q-q0)2 for q≠q0 . These predictions can be tested experimentally by suitable transient spin grating experiments.
- Publication:
-
Physical Review B
- Pub Date:
- October 2010
- DOI:
- 10.1103/PhysRevB.82.155324
- arXiv:
- arXiv:1008.0132
- Bibcode:
- 2010PhRvB..82o5324Y
- Keywords:
-
- 72.25.-b;
- 72.10.-d;
- Spin polarized transport;
- Theory of electronic transport;
- scattering mechanisms;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- Phys. Rev. B 82, 155324 (2010)