English

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

Mesoscale and Nanoscale Physics 2015-03-19 v1

Abstract

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 where 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.

Keywords

Cite

@article{arxiv.1111.3624,
  title  = {Mach-Zehnder Interferometric device for spin filtering in a GaAs/AlGaAs electron gas},
  author = {Benjamin Santos and Ernesto Medina and Alexander López and Bertrand Berche},
  journal= {arXiv preprint arXiv:1111.3624},
  year   = {2015}
}