11:00 AM, April 7, 2011
Sumwalt, Room 120A

Dr. Valeriy Slipko

Radial Spin Helix in Two-Dimensional Electron Systems 
with Rashba Spin Orbit Coupling

We suggest a long-lived spin polarization structure, a radial spin 
helix, and study its relaxation dynamics. For this purpose, starting 
with a simple and physically clear consideration of spin transport, we 
derive a system of equations for spin polarization density and find its 
general solution in the axially symmetric case. It is demonstrated that 
the radial spin helix of a certain period relaxes slower than 
homogeneous spin polarization and plain spin helix. Importantly, the 
spin polarization at the center of the radial spin helix stays almost 
unchanged at short times. At longer times, when the initial non-
exponential relaxation region ends, the relaxation of the radial spin 
helix occurs with the same time constant as that describing the 
relaxation of the plain spin helix. 

Paper: 
Yu. V. Pershin, V. A. Slipko, Physical Review B 82, 125325 (2010)
http://arxiv.org/pdf/1007.0853v1