Structural, elastic, and electronic properties of cubic zinc-blende InxGa1−xN alloys

The cubic phase of the ternary ${\mathrm{In}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{N}$ alloy has attracted significant interest as a material for next-generation high-performance electronic and optoelectronic applications. It has recently been demonstrated that epitaxial growth techniques can overcome the miscibility gap in this alloy system, thereby revealing the existence of CuPt-type ordering around $x\ensuremath{\approx}0.5$ [ACS Appl. Mater. Interfaces 15, 39513 (2023)]. We present a comprehensive theoretical analysis of the structural and electronic properties of the (In, Ga)N alloy in the zinc-blende structure. This study covers both pure phases of InN and GaN, as well as random alloys of ${\mathrm{In}}_{x}{\mathrm{Ga}}_{1\ensuremath{-}x}\mathrm{N}$. Furthermore, it examines the composition of ${\mathrm{In}}_{0.5}{\mathrm{Ga}}_{0.5}\mathrm{N}$ in the ordered phases with CuPt-type ordering and chalcopyrite-type ordering. We establish that the investigated structures are metastable. The results presented include the lattice parameters, elastic constants, and the phononic and electronic band structures. We compare the random phase with the ordered structures and report how the structure affects the properties. This results facilitate the differentiation between the phases in experimental settings.