Prediction of lower current threshold in tensile strained ZnCdSe/ZnMgSSe multiple quantum well blue-green lasers

Gain coefficient involving excitonic transitions is calculated for unstrained as well as strained ZnCdSe/ZnMgSSe multiple quantum well (MQW) lasers as a function of operating wavelength and current density. This paper models the behavior of radiative recombination involving excitons as well as free carriers in strained layer blue-green quantum well lasers, and predicts for the first time a low threshold operation in tensile strained active layers. For example, the tensile strained Zn _.8Cd_.2Se-ZnMgSSe quantum well lasers are shown to operate at threshold current density as low as 180 A/cm², which is about the half of the compressive strain case