Effect of band anticrossing on the optical transitions in ${\mathrm{GaAs}}_{1-x}{\mathrm{N}}_x/\mathrm{GaAs}$ multiple quantum wells

Interband transitions in ${\mathrm{GaAs}}_{1-x}{\mathrm{N}}_x/\mathrm{GaAs}$ multiple quantum wells were studied at room temperature by photomodulated reflectance spectroscopy as a function of well width (3–9 nm), the nitrogen concentration $\mathrm{}(0.012<x<\mathrm{}0.028\mathrm{}),$ and hydrostatic pressure (0–64 kbar). All experimental data can be quantitatively explained using the dispersion relationship obtained from a band anticrossing model to calculate electron confinement effects in a finite depth quantum well. The results are consistent with a nitrogen-induced large increase of the electron effective mass in the GaAsN quantum wells.