Electrically injected spin-polarized vertical-cavity surface-emitting lasers

We report the design, fabrication, and characterization of an electrically injected, spin-polarized, vertical-cavity surface-emitting laser. We have demonstrated spin injection from the ferromagnetic semiconductor (Ga,Mn)As into In0.2Ga0.8As/GaAs quantum wells, spin transport across a distance of similar to 0.25 mu m for temperatures ranging from 80 to 105 K, and spin detection through optical polarization measurements with coherent light emission. Controlled switching between right- and left-elliptically polarized modes is achieved with a maximum degree of circular polarization of 4.6% measured at 80 K. (c) 2005 American Institute of Physics.