A force-matching method is employed to optimize the parameters of the Stillinger-Weber (SW) interatomic potential for calculation of the lattice thermal conductivity of silicon. The parameter fitting is based on first-principles density functional calculations of the restoring forces for atomic displacements. The thermal conductivities of bulk crystalline Si at 300-500 K estimated using nonequilibrium molecular dynamics with the modified parameter set show excellent agreement with existing experimental data. We also briefly discuss how the force-matching-based parameterization can provide the improved estimation of thermal conductivity, as compared to the original SW parameter set, through analysis of phonon density of states and phonon dispersion relations.
|Physical Review B - Condensed Matter and Materials Physics
|Published - 22 Mar 2012