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

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. (C) 1998 Elsevier Science B.V. All rights reserved.