The role of pressure on lattice thermal conductivity and its related thermodynamical parameters in In0.53Ga0.47As nanofilms.

Abstract

Lattice thermal conductivity (LTC) for In0.53Ga0.47As alloy films, with thicknesses ranging from 10 nm to 1.4 μm, was investigated under pressures of up to 11 GPa and temperatures between 1 and 450 K, utilizing the modified Debye-Callaway model. The effects of structural and thermodynamical parameters, as well as phonon interactions, on LTC were examined. The Clapeyron, Murnaghan, and Post equations were applied to determine the pressure dependence of the melting temperature, lattice volume, and Debye temperature, respectively. A novel derivative form of the bulk modulus, suitable for nanomaterials, has been introduced. It was found that decreasing the film thickness increases the Gruneisen parameter, while increasing pressure decreases it. The LTC of nanofilms is significantly affected by their thickness and pressure strength; notably, under 11 GPa, films with a thickness of 10 nm exhibit a substantial decrease in LTC. LTCmax declines due to the greater influence of boundary scattering compared to dislocations. These findings suggest potential applications in managing nanofilm temperature and size, which are key to advancing nanomaterials and enhancing the efficiency of electronic devices.