Lasing mechanisms and optical gain in visible-bandgap II-VI quantum well structures

The origin of lasing in (Zn,Cd)Se/ZnSe quantum well structures is elucidated in a temperature range between 5 and 300 K. We observe very large bi-exciton gain (2.5/spl middot/10/sup 4/ cm/sup -1/), turning into less efficient electron-hole plasma recombination above 160 K.