Abstract
A model is developed to describe the pressure dependence of the band gap energy for the dilute nitride GaNxAs1–x. It is found that the sublinear pressure dependence of E− is due to the coupling interaction between E+ and E−. We have also found that GaNxAs1−x needs much larger pressure than GaAs to realize the transition from direct to indirect band gap. It is due to two factors. One is the coupling interaction between the E+ and E−. The other is that the energy difference between the X conduction band minimum (CBM) and the G CBM in GaNxAs1−x is larger than that in GaAs. In addition, we explain the phenomenon that the energy difference between the X CBM and the G CBM in GaNxAs1−x is larger than that in GaAs. It is due to the impurity-host interaction.