Mach-Zehnder interferometric device for spin filtering in a GaAs/AlGaAs electron gas

Benjamin Santos, Ernesto Medina, Alexander López, Bertrand Berche
2011 Journal of Applied Physics  
A spin filtering device using quantum spin interference is theoretically proposed in a GaAs/AlGaAs electron gas that has both Rashba and Dresselhaus spin-orbit couplings. The device achieves polarized electron currents by separating spin up and spin down components without a magnetic field gradient. We find two broad spin filtering regimes, one where the interferometer has symmetrical arms, where a small magnetic flux is needed to achieve spin separation, and the other with asymmetric arms
more » ... the change in path length renders an extra phase emulating the effects of a magnetic field. We identify operating points for the device where optimal electron polarization is achieved within value ranges found in a 2D electron gas. Both device setups apply for arbitrary incoming electron polarization and operate at broad energy ranges within the incoming electron band.
doi:10.1063/1.3665702 fatcat:begrzfe3rja5xg6duv4bjlbkba