Characteristics of a high temperature vertical spin valve

We demonstrate high temperature electrical spin injection and detection in degenerately p-doped GaAs in vertical spin valves using valence band electron tunneling. The maximum measured magnetoresistance at 10 and 300 K is 40% and similar to 1%, respectively. Spin relaxation in these devices was found to be relatively insensitive to temperature (T) for T> 125 K. The spin injection and detection efficiencies are mostly dominated by the ferromagnetic contact polarization and spin independent transport at the ferromagnet/semiconductor interface. (C) 2010 American Institute of Physics. [doi:10.1063/1.3524820]