Papers by Keyword: Lattice Thermal Conductivity

Abstract: Understanding and controlling the phonon, the dominant heat carrier of semiconductor materials, is essential to developing a wide variety of applications. This article studies the theoretical and computational approach of the calculation of lattice thermal conductivity of semiconducting materials. Despite having different methods to calculate the lattice thermal conductivity, first-principle estimates predict more accurately in most applications. This motivates to present the descriptive explanation on first-principle calculation with the combination of lattice dynamics and Boltzmann transport equation. Finally, we summarized an overview of the recent achievements and opportunities.

Abstract: The wide range of industrial applications is the main reason for an increased interest in dioxides such as HfO₂. In this study, classical molecular dynamic simulations were performed to calculate the lattice thermal conductivity of the cubic phase of HfO₂, over a temperature range of 100-3000 K, based on the Green-Kubo fluctuation method. In this research, the heat current autocorrelation function and lattice thermal conductivity were calculated in the a-direction. The lattice thermal conductivity of the cubic phase of HfO₂ was found to be a result of three contributions. These were the optical and acoustic short-range and long-range phonon modes. Comparisons between the results of the research and experimental data when available indicate good agreement. Keywords: lattice thermal conductivity, molecular dynamics, Green-Kubo formalism, heat current autocorrelation function, hafnium dioxid

Abstract: Single-phase double atoms filling skutterudite compounds were synthesized by using melting reaction method. The effects of double atoms filling on the structure and lattice thermal conductivity of skutterudite compounds were investigated. The results of Rietveld refinement indicate that CamCenFexCo4-xSb12 compounds possess skutterudite structure and the Sb-icosahedron voids have been partially filled with filling atoms. With the same filling fraction, the lattice thermal conductivity of CamCenFexCo4-xSb12 is smaller than that of CamFexCo4-xSb12 and CenFexCo4-xSb12, furthermore, when the total filling fraction (m+n) is about 0.3 and respective filling fraction of Ca and Ce are approximately equal, the lattice thermal conductivity is the least.