The effect of AlGaN bulk and AlGaN/GaN superlattice cladding layers on performance characteristics of deep violet InGaN DQW lasers

This paper reports performance characteristics of InGaN-based DQW laser diodes with different SLS cladding layer (CL) structures using the ISE TCAD software. LDs with SLSs as CLs were shown to have superior optical and electrical properties compared to LDs with bulk AlGaN CLs.The simulation results show the variation of output power, threshold current, slope efficiency, and differential quantum efficiency (DQE) from 13.51 to 10.88 mA, 20.92 to 41.27 mW, 1.83 to 1.87 W/A and 57.88 to 59.10%, for bulk to SLS CLs. Results show the increased operating current, electron and hole carrier densities and radiative recombination which enhanced output power and reduced threshold current for the structure with the SLS down CL. Using SLS in upper CL doesn't have significant effect on operating current, it increase the slope efficiency and DQE. Using SLS structure simultaneously in up and down CLs enhances the output power, DQE and slop efficiency, and decreases the threshold current.