Excitation Density Dependence of Photoluminescence and Barrier Doping Effect in InxGa1—xN Quantum Wells

Abstract

The effect of Si-doping in barriers has been investigated in photoluminescence (PL) spectra of 10 period In0.1Ga0.9N/ In0.02Ga0.98N quantum wells with various excitation densities. For the quantum wells with well width of 40 A, the PL peak was blueshifted and the intensity was increased with Si-doping under relatively low excitation density. However, such Si-doping effect was found to be less pronounced with higher excitation density. The blueshift of PL emission with increasing excitation density was larger for larger well widths, which indicates the influence of a piezoelectric potential in our samples. For sufficiently narrow quantum wells, we observed a redshift with increasing excitation density due to the bandgap renormalization effect.