Photo-induced interband absorption in group-III nitride quantum wells
Résumé
We solve self-consistently Schrödinger and Poisson equations for GaN/AlGaN quantum wells, to analyze the change of optical spectra under high optical excitation. Electric fields of Full-size image ~1 MV/cm or higher are present along the growth axis of such quantum wells. The induced separation of electron and hole wave functions reduces the oscillator strength of the ground-state optical transition, whereas those involving excited states give a much larger absorption. In presence of large electron–hole pair densities, we show that the optical density can be either reduced or enhanced, depending on the spectral region involved.