Boundary conditions for semiclassical spin-hall effects

Yaroslav Tserkovnyak

Department of Physics and Astronomy, University of California, Los Angeles, USA

The question of existence of electrically-induced transverse spin currents in systems with intrinsic spin-orbit coupling has recently been extensively studied, but a number of important experimentally relevant issues still remain. One of them is the possibility to induce and detect nonequilibrium spin accumulation at the Hall-bar edges. In order to calculate it in the semiclassical regime, the coupled spin-charge diffusion equations for the bulk transport have to be complemented with appropriate boundary conditions, which turns out to be a task with amusing subtleties. I will discuss how to generically derive such boundary conditions in a rather straightforward and physical manner.