  We report electrical control of the spin polarization of InAs/GaAs
self-assembled quantum dots (QDs) at room temperature. This is achieved by
electrical injection of spin-polarized electrons from an Fe Schottky contact.
The circular polarization of the QD electroluminescence shows that a 5%
electron spin polarization is obtained in the InAs QDs at 300 K, which is
remarkably insensitive to temperature. This is attributed to suppression of the
spin relaxation mechanisms in the QDs due to reduced dimensionality. These
results demonstrate that practical regimes of spin-based operation are clearly
attainable in solid state semiconductor devices.
