Investigation on Structural, Electronic, Thermal, and Thermoelectric Properties of Co-=SUB=-2-=/SUB=-MnGa under Pressure Based on Density Functional Theory

Abstract

Structural, electronic, thermal, and thermoelectric properties of Co2MnGa under 0, 5, 10, and 15 GPa pressures have been investigated. In electronic properties, in minority spin, a pseudo band gap (about 0.25 eV) is visible. Thermal properties in the range of 0 to 700 K have been calculated. Our results in thermal properties have a good agreement with another theoretical work. Calculations of thermoelectric properties, in both spin up and down, in the range of 100 to 700 K have been done. In spin up, an abnormal behavior is observed under 5 GPa for electrical conductivity. This is due to increase in Mt at this pressure. The sign and value of Seebeck coefficient in spin up at 300 K has a good consistency with experimental work. Other thermoelectric properties such as: power factor, electronic thermal conductivity divided by relaxation time, electronic contribution of heat capacity at constant volume under pressure have been studied. Keywords: Co2MnGa, density functional theory, electronic properties under pressure, thermoelectric properties under pressure.