Advantages of InGaN-GaN-InGaN Delta Barriers for InGaN-Based Laser Diodes

An InGaN laser diode with InGaN-GaN-InGaN delta barriers was designed and investigated numerically. The laser power-current-voltage performance curves, carrier concentrations, current distributions, energy band structures, and non-radiative and stimulated recombination rates in the quantum wells were characterized. The simulations indicate that an InGaN laser diode with InGaN-GaN-InGaN delta barriers has a lower turn-on current, a higher laser power, and a higher slope efficiency than those with InGaN or conventional GaN barriers. These improvements originate from modified energy bands of the laser diodes with InGaN-GaN-InGaN delta barriers, which can suppress electron leakage out of, and enhance hole injection into, the active region.