Density Functional Theory Studies of the Electronic and Optical Properties of Zinc Blende InN under High Pressure

First-principles density functional studies of the properties of zinc blende InN are presented. We have employed density functional theory, as implemented in the CASTEP code, to investigate the electronic, elastic and optical properties of the material zinc blende InN under hydrostatic pressure range up to 70 GPa. The optimized geometrical lattice constant of InN in the ground state obtained by using generalized gradient approximation is in good agreement with existing results and the lattice constants with pressure increasing. The calculated partial densities of states (PDOS) of the material have two regions in the valence band of InN. It is shown that the PDOS is quite low in the vicinity of the Fermi level, implying that it tends to form stable structure but has a poor conductivity. The elastic tensor components have linear scaling with pressure, C11, C12 and B have a positive scaling with pressure. Whereas C44 and Cs have a negative scaling. The absorption spectra move towards the shorter wavelength direction. The shape of the spectra has almost no change when pressure increases. The results presented in this workare helpful for re-evaluating much of the pressure dependence of the properties for the material InN.