Spin polarized lasers

The ability to dynamically switch between orthogonal polarization states in spin-polarized semiconductor lasers with the bias current, which are otherwise difficult to predict, stabilize, or control, offers a novel and elegant technique for secure communication in a lightwave network. Other envisaged applications include reconfigurable optical interconnects, study of vitamins and asymmetric photochemical synthesis. Spin-polarized lasers also promise reduced threshold current [2], enhanced emission intensity and optical communication with enhanced bandwidth. For practical purposes the lasers have to be electrically injected and operate at high temperatures. To this end we have investigated the properties of quantum well and quantum dot spin vertical cavity surface emitting lasers (spin-VCSELs).