First principle study of the physical properties of semiconducting binary antimonide compounds under hydrostatic pressures

Abstract

First-principle calculations have been performed to investigate the structural phase transition, electronic, elastic, thermodynamical and optical properties of III-Sb compounds under hydrostatic pressure up to their first order transitions pressure (Zinc Blende to Rock Salt). Four different exchange–correlation functionals comprising Perdew–Burke–Ernzerhof generalized parameterization of gradient approximation, Wu-Cohen, local density approximation as well as modified Becke and Johnson were used. The structural properties such as phase transitions, equilibrium lattice parameters, bulk modulus and its first pressure derivative were obtained using an optimization method. Moreover, elastic constants, Young׳s modulus, shear modulus, Poisson׳s ratio, sound velocities for longitudinal and shear waves, Debye average velocity, Debye temperature and Grüneisen parameters were calculated up to the first order phase transition pressure. The obtained structural and elastic parameters are consistent with the available experimental data. The static calculations predict that Zinc Blende to Rock Salt phase transitions occur at 48.5, 9.5, 5.87 and 3.15GPa for BSb, AlSb, GaSb and InSb respectively. The optical properties of these compounds, such as dielectric function, refractive index and the optical band gap were also calculated for the radiation up to 14eV. In addition, the influence of the hydrostatic pressure on the elastic parameters, energy band structures and the refractive index of these compounds were investigated. The linear and quadratic pressure coefficients of the compounds were also calculated. Results have been discussed and compared with available experimental and theoretical data, which show an overall good agreement with the other studies.