Rashba Spin-Orbit-Coupling Based Electron-Spin Filter in Double-Layered Semiconductor Nanostructure

Based on a double-layered semiconductor nanostructure (DLSN)-InSb/GaSb, we propose a controllable electron-spin filter for spintronics device applications. Electron-spin polarization is induced by Rashba spin-orbit coupling inside the DLSN. Both magnitude and sign of spin polarization ratio can be manipulated by externally-applied electric field or the semiconductor-layer thickness.