STIMULATED BLUE EMISSION PROCESSES IN ZN1-XCDXSE ZNSE MULTIQUANTUM WELLS/

Stimulated emissions in Zn1-xCdxSe/ZnSe multi-quantum well (MQW) struc tures have been studied under high optical excitation in the temperatu re range 4.2-300 K. With increasing the excitation intensity, the stim ulated emission at low temperatures shows a red shift of the peak ener gy and a quadratic dependence of the intensity on the excitation inten sity. The observed stimulated emission process is interpreted by excit on-exciton scattering in the MQWs. At room temperature, highly excited MQWs show a markedly broadened emission, the intensity of which is in proportion to the excitation intensity. We attribute the emission pro cess to electron-hole plasma (EHP) recombination. The observed emissio n spectra are in good agreement with calculations by using models of e xciton-exciton scattering and EHP recombination. The stimulated emissi on mechanisms elucidated in the present study are closely related to t hose tailing place in ZnSe-based blue laser diodes.