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.