Pressure behavior of InxGa1−xAs/GaAs strained quantum wells with different widths

The photoluminescence of In x Ga 1−x As/GaAs strained quantum wells with widths of 30 A to 160 A have been studied at 77 K under hydrostatic pressure up to 60 kbar. It is found that the pressure coefficients of exciton peaks from 1st conduction subband to heavy hole subband increase from 9.74 meV/kbar for a 160 A well to 10.12 meV/kbar for a 30 A well. The calculation based on the Kronig-Penney model indicated that the extension of the electronic wave function to the barrier layer in the narrow wells is one of the reasons for the increase of the pressure coefficients with the decrease of well width