A set of ${(\mathrm{Ga}}_{0.77}{\mathrm{In}}_{0.23})\mathrm{As}∕\mathrm{Ga}({\mathrm{N}}_x{\mathrm{As}}_{1-x})$ heterostructures is studied by time-resolved photoluminescence. Four samples with nitrogen concentrations from $x=0.48\%$ up to $x=2.2\%$ are investigated at different temperatures and with different excitation densities. The experiments suggest that the heterostructure band offset is type I for $x=0.48\%$ and type II for $x=2.2\%$. The situation is more complex for $x=0.72\%$ and $x=1.25\%$, since these samples are close to the transition from type I to type II. The experimental findings are analyzed using a detailed microscopic theory. Numerical calculations describe the measured data well. In particular, the interpretation of the experimental results concerning the band alignment is confirmed by the theoretical analysis.

• Received 8 October 2004

DOI:https://doi.org/10.1103/PhysRevB.71.165320