OBSERVATION OF BIEXCITONIC EFFECT IN SINGLE ZNCDSE QUANTUM-WELL UNDERVERY-LOW EXCITATION DENSITY

Under an excitation density of 0.4 W/cm(2), a strong biexcitonic peak was observed in the photoluminescence (PL) spectrum of a single quantu m well which was grown in submonolayer deposition mode. Its intensity was found to increase superlinearly with excitation density. The shape of the biexcitonic peak was found to be similar to that of biexcitons in CuCl and CdS crystal and a binding energy of 9.8 meV was obtained. When the temperature increased from 10 to 31 K, the biexcitonic peak decreased considerably whereas the excitonic peak increased slightly. (C) 1997 American Institute of Physics.