Heat conduction theory including phonon coherence
arXiv:2110.09750 · doi:10.1103/PhysRevLett.128.015901
Abstract
Understanding and quantifying the fundamental physical property of coherence of thermal excitations is a long-standing and general problem in physics. The conventional theory, i.e. the phonon gas model, fails to describe coherence and its impact on thermal transport. In this letter, we propose a general heat conduction formalism supported by theoretical arguments and direct atomic simulations, which takes into account both the conventional phonon gas model and the wave nature of thermal phonons. By naturally introducing wavepackets in the heat flux from fundamental concepts, we derive an original thermal conductivity expression including coherence times and lifetimes. Our theory and simulations reveal two distinct types of coherence, i.e., intrinsic and mutual, appearing in two different temperature ranges. This contribution establishes a fundamental frame for understanding and quantifying the coherence of thermal phonons, which should have a general impact on the estimation of the thermal properties of solids.
arXiv comment5 pages, 3 figures
References in corpus (12)
- Moment Tensor Potentials: a class of systematically improvable interatomic potentials
- Optimized Tersoff and Brenner empirical potential parameters for lattice dynamics and phonon thermal transport in carbon nanotubes and graphene
- Thermal Properties of Isotopically Engineered Graphene
- Unified theory of thermal transport in crystals and disordered solids
- Efficient molecular dynamics simulations with many-body potentials on graphics processing units
- Modeling heat transport in crystals and glasses from a unified lattice-dynamical approach
- Heat conduction tuning using the wave nature of phonons
- Thermal transport in crystals as a kinetic theory of relaxons
- Phonon Hydrodynamic Heat Conduction and Knudsen Minimum in Graphite
- A revisit to phonon-phonon scattering in single-layer graphene
- Phonon Dispersion Effects and the Thermal Conductivity Reduction in GaAs/AlAs Superlattices
- A generalized decay law for particle- and wave-like thermal phonons