Voltage induced spin density in a double quantum well with inversion asymmetry

We study spin polarization induced by an applied bias in a bilayer quantum well system with interlayer spin–orbit coupling. The bias is incorporated via the non-equilibrium Greenʹs function formalism, which allows us to handle a variety of system configurations. We shall focus on the component of the spin density perpendicular to the bilayer and compare our results to those obtained for a single layer system.