Evidence of the correlation between a strong 4d-As/2p-N orbitals coupling and the bowing effect in GaAsN

By means of a simple physical argumentation, we found that the giant bowing observed in GaAsN is correlated to the interaction between 4d-As and 2p-N orbitals. The calculations were carried out within the first principles full potential linear muffin-tin orbitals (FPLMTO) method in its plane wave approximation (PLW) which enables an accurate treatment of the interstitial regions. The choice of this method ensures our work to be free from adjustable parameters and enabled us to perform a microscopic study.