ABSTRACT
The thermal conductivity is a fundamental thermal transport parameter that describes the ability of a material to conduct heat. This chapter focuses on ab initio theoretical approaches to calculate the lattice thermal conductivity κ, where heat is carried by phonons. Thermal conductivity κ determines the utility of materials for specific thermal management applications. Materials with low thermal conductivity find applicability in, for example, efficient thermoelectric (TE) cooling and power generation devices, while materials with high thermal conductivity are needed for passive cooling of microelectronics. If modes with small density of states substantially contribute to heat conduction, as occurs in silicon, these phonons are unlikely to be sampled, leading to large noise for certain phonon frequencies. The task of engineering phonon transport is particularly difficult because of the lack of simulation tools to describe heat conduction in the complex microstructure of realistic TE crystals.
