Performance enhancement of AlGaN deep-ultraviolet laser diodes with linear variation quantum barriers

This paper proposes quantum barriers (QBs) with linearly decreasing/increasing Al molar fraction to improve the performance of AlGaN-based deep ultraviolet laser diodes (DUV-LDs). The effects of the QBs with constant Al molar fraction and the QBs with linearly changing Al molar fraction on the LDs performance are numerically investigated. The QBs with linearly changing Al molar fraction reduce the threshold voltage of the LDs, and increase the carrier injection efficiency, the carrier concentration in the quantum well region, the stimulated recombination rate, and the output power of the device, which is significant for the application and development of AlGaN materials in DUV-LDs.