Indium distribution and light emission in wurtzite InGaN alloys: Several-atom In-N clusters

Considering various In distributions, we investigate electronic structures and light emission of wurtzite InxGa1 − xN (0⩽x⩽10⩽x⩽1) alloys. We find InxGa1 − xN forms a random alloy, in which many several-atom In-N clusters and short In-N- chains can exist. Small In-N clusters, especially in-plane ones, strongly localize valence electrons and dominate light emission in Ga-rich InxGa1 − xN alloys, which is consistent with experiments.