Electron and phonon interactions and transport in ultra-high-temperature ceramic ZrC

We have simulated the ultra-high-temperature ceramic zirconium carbide (ZrC) in order to predict electron and phonon scattering properties, including lifetimes and transport. Our predictions of heat and charge conductivity, which extend to 3000 K, are relevant to extreme temperature applications of ZrC. Mechanisms are identified on a first principles basis that considerably enhance or suppress heat transport at high temperature, including strain and anharmonicity. The extent to which boundary confinement and isotope scattering effects lower thermal conductivity is predicted.