Pressure-induced phase transition and electronic properties of AlN nanowires: an ab initio study

The structural stability of AlN nanowires have been analyzed in wurtzite (B4), zincblende (B3), rocksalt (B1) and CsCl (B2) type phases using density functional theory based ab initio approach. The total energy calculations have been performed in a self-consistent manner using local density approximation as exchange correlation functional. The analysis finds the B4 type phase as most stable amongst the other phases taken into consideration and observes the structural phase transition from B4B3, B4B1, B4B2, B3B1 and B3B2 at 42.7, 76.54, 142, 30.4 and 108.9GPa respectively. Lattice parameter, bulk modulus and pressure derivatives of AlN nanowires have also been calculated for all the stable phases. The electronic band structure analysis of AlN nanowires shows a semiconducting nature in its B4, B3 and B1 type phases, whereas the B2 type phase is found to be metallic.