Pressure and Temperature Dependent Studies of GaNxAs1-x/GaAs Quantum Well Structures

The pressure and temperature dependence of quantum well transitions in GaNxAs1—x/GaAs quantum well structures with xN = 1.8% and various well widths grown by metal organic vapour phase epitaxy were studied by photomodulated reflectance (PR) spectroscopy. The quantum well transition energies and their pressure dependence can be well described by a ten-band k · p Hamiltonian. Comparing experiment and theory demonstrates that the band alignment of the quantum well structures is type I with a chemical valence band offset of about 30% ± 5% for xN = 1.8%. The temperature coefficients of the quantum well states are to a good approximation independent of well width and considerably smaller than that of GaAs.