Optical Gain in AlGaN Quantum Wells: Impact of Higher Energy States

Simulations of optical gain in aluminum gallium nitride (AlGaN) quantum wells are extended to the high charge carrier density regime required for achieving gain at 275 nm for UV laser diodes. Coulomb interaction is modeled using the 2nd Born approximation. We demonstrate good agreement with experimental data obtained through optical pumping, and predict gain spectra for electrical pumping. Special consideration is given to the contribution of higher bands in wide quantum wells.