GaN/AlGaN SCH UV semiconductor lasers: Effect of GaN well thickness on lasing efficiency

Summary form only given. GaN active medium structures are attracting much attention for the development of UV laser diodes (LDs) with emission wavelengths lying below 370 nm. We previously reported a significant reduction of the stimulated emission (SE) threshold in GaN/AlGaN SCHs compared to bulk GaN layers and identified the gain mechanisms. In this study, we investigated the effect of the GaN well thickness, which is a crucial design parameter, on the SE behavior. Built-in internal electric fields (intrinsic to GaN-based structures) reduce the emission efficiency, and this decrease in efficiency is greater for larger GaN well thicknesses. We measured 10 K photoluminescence (PL) spectra of SCH samples with well thicknesses of 3, 5, 9, and 15 nm.