Spin injection and detection in a ferromagnetic metal/2DEG structure

Spin dependent transport in a high mobility two dimensional electron gas (2DEG) with an asymmetric confining potential is observed by using a ferromagnetic metal as a spin sensitive voltage probe. A high impedance junction is formed between the ferromagnet and the 2DEG on a planarized sample. The conduction band of the 2DEG is split into spin subbands by the Rashba effect, and nonequilibrium magnetization is induced by a bias current. The magnetization of the ferromagnet is controlled by an external magnetic field, and the voltage sensed in each of its two magnetic states corresponds to the up- and down-spin subband chemical potentials of the 2DEG carriers.