Photoluminescence investigation of InGaN/GaN single quantum well and multiple quantum wells

Abstract

The photoluminescence investigation at a low temperature was carried out in ${\mathrm{In}}_{\mathrm{0.13}}{\mathrm{Ga}}_{\mathrm{0.87}}\mathrm{N/GaN}$ single quantum well (SQW) and multiple quantum wells with 10 (10QW) or 5 periods. With decreasing number of wells, the emission peak shows a redshift. In the case of a low excitation power, the emission intensity is enhanced by an increase in the number of wells while it decreases in the case of a high excitation power. With increasing excitation power, the emission peak of the SQW exhibits a blueshift and its linewidth decreases, but the emission peak of the 10QW remains unchanged and its linewidth increases. Based on the theory of the quantum confined Stark effect, the behavior of the SQW and the 10QW can be well explained. This result should be highly emphasized in designing InGaN/GaN based optical devices.