Heat transport in silicon from first principles calculations

Understand

Using harmonic and anharmonic force constants extracted from density-functional calculations within a supercell, we have developed a relatively simple but general method to compute thermodynamic and thermal properties of any crystal.

• First, from the harmonic, cubic, and quartic force constants we construct a force field for molecular dynamics (MD).
• It is exact in the limit of small atomic displacements and thus does not suffer from inaccuracies inherent in semi-empirical potentials such as Stillinger-Weber's.
• By using the Green-Kubo (GK) formula and molecular dynamics simulations, we extract the bulk thermal conductivity.