Can Amorphous GaN Serve as a Useful Electronic Material?

In this paper, we propose two structural models of amorphous GaN at different densities, obtained from approximate ab initio molecular dynamics. The network models we obtain are highly disordered but exhibit a large state-free optical gap, and have no homopolar bonds (or odd-membered rings). The radial distribution function, local bonding, and electronic density of states are described. We find that a model with many threefold atoms has weakly localized band tails, especially at the valence edge. This leads us to believe that amorphous GaN may have independent promise as a novel electronic material. [S0031-9007(97)03647-8]