Rashba Hamiltonian and electron transport - art. no. 121202

The Rashba Hamiltonian describes the splitting of the conduction band as a result of spin-orbit coupling in the presence of an external field and is c ommonly used to model the electronic structure of confined narrow-gap semic onductors. Due to the mixing of spin states some care has to be exercised i n the calculation of transport properties. We derive the velocity operator for the Rashba-split conduction band and demonstrate that the transmission of an interface between a ferromagnet and a Rashba-split semiconductor does not depend on the magnetization direction, in contrast with previous asser tions in the literature.