ABSTRACT
This chapter is devoted to key processes which determine spin injection efficiency in the spin light-emitting diodes from ZnMnSe/Zn(Cd)Se quantum well structures. The polarization of the hot photoluminescence (PL) line, obtained after subtracting the contribution from the broad PL band, has the same sign as the lower spin state but is opposite to that of the pumping light. In optical spin orientation experiments, a preferred spin orientation of excitons and charge carriers is generated by a corresponding circularly polarized light without application of an external magnetic field. The efficiency of spin injection in light-emitting diode structure during electrical and optical injection was evaluated from the polarization of light emission measured by electro-luminescence or or PL. ZnO and related alloys are attracting increasing attention since they are excellent candidates for use in visible and ultraviolet light emitters, in transparent electronics, and also in chemical and bio sensing.
