Impact of Al interdiffusion on optical properties in GaSb/AlGaSb multiple quantum wells

Abstract We have studied the effect of the Al interdiffusion on the electronic states of AlGaSb–GaSb quantum wells. Measuring the interdiffusion lengths by means of highly depth-resolved secondary ion mass spectrometry we find that the effect of Al diffusion results in the transformation of the ternary–binary system in a ternary–ternary structure. The modified energy levels, calculated on the basis of the measured chemical profile using a Posch–Teller potential, are consistent with the blue shifts of the PL peaks measured in samples grown with increasing growth temperature.