Abstract
The band gaps of the GaInAsN alloys lattice-matched to GaAs and InP have been calculated as a function of the nitrogen composition and as a function of pressure, by using a pseudopotential technique. The calculations are in excellent agreement with the experimental results, which are only available for small nitrogen compositions. The band gap of both lattice-matched systems is predicted to significantly decrease when further increasing the nitrogen content. As a result, the band gap of both systems closes for large enough nitrogen compositions (around 12%–20%).