Near-Room-Temperature Photopumped Blue Lasers in ZnS_xSe_1-x/ZnSe Multilayer Structures

Abstract

Photopumped blue laser oscillation was achieved up to near room temperature (280 K) in a ZnS 0.18 Se 0.82 /ZnSe multilayer structure grown by MOVPE. This significant improvement in the lasing temperature is attributed to the higher heterobarrier which prevents thermoionic emission and to the multilayer structure which has an average lattice constant matched to the GaAs substrate at the growth temperature of 515°C. The threshold excitation optical power density below 200 K where the thermoionic emission is negligible is less than 50 kW/cm 2 , which corresponds to a current density of 14 kA/cm 2 .