Electrical driving single barrier spin cell
  We propose a spin cell based on photon-assisted tunneling through a conventional semiconductor barrier. The Dresselhaus spin-orbit interaction is included to break the spin rotation symmetry. Due to the in-plane electric field induced asymmetric momentum distribution in one lead, continuous flows of spin currents are driven through a barrier by a AC field. The net charge current remains zero. The spin current via photon-assisted tunneling can be readily adjusted via tuning the AC frequency or the in-plane electric field. This device may function as an ideal spin cell to supply spin currents in the spintronics circuit. 
B. H. Wu, and Kang-Hun Ahn