Photoluminescence and photoluminescence excitation spectra of In/sub 0.2/Ga/sub 0.8/N-GaN quantum wells: comparison between experimental and theoretical studies

InGaN-GaN represents an important heterostructure with applications in electronics and optoelectronics. It also offers a system where we can study the effects of interface roughness, alloy clustering, and the piezoelectric effect. In the paper, we examine how these factors influence the photoluminescence and excitation photoluminescence in InGaN-GaN quantum wells. We examine the Stokes shift as a function of the excitation level and doping and relate the values to the piezoelectric effect and disorder in the system. Detailed comparisons are made with experimental results.