Résumé
The efficiency of nitride‐based optical devices, with particular focus on Al x Ga 1‐ x N/AlN quantum wells used for deep ultraviolet light emission is investigated. The study addresses the wavelength dependence of the photoluminescence and in particular the drop in efficiency as the emission wavelength decreases from 250 nm to 210 nm. A model is developed that incorporates the effects of hole state symmetry changes, built‐in strain, quantum confinement, and 2D electron‐hole localization. The latter is introduced as a Gaussian potential representing the spatial alloy disorder in the heterostructures. This model shows good agreement with experimental data and emphasizes that the localization mechanism is crucial for understanding the light emission behavior.