Anharmonic Phonons are Heating Up

[vanceeasleaf]

Anharmonic Phonons are Heating Up
The importance of anharmonicity in the atomic vibrations of crystalline materials has long been known, but the quantities involved have been prohibitively expensive to calculate from first-principles. It is now becoming possible to accurately predict properties including thermal expansion, thermal conductivity, phonon lifetimes, frequency shifts, and displacive phase transitions, for increasingly complex materials.

Last week, I attended a stimulating workshop on anharmonicity in Paris (funded by CECAM) that collected many leaders in the field. Below is a summary of the selection of currently available techniques and codes. For a primer on the history of the field, I recommend The rise of self-consistent phonon theory by Klein and Horton (1972).

AFLOW-AAPL – Automation of phonon calculations and thermal conductivity: [code]; [paper]
Alamode – High-order force constants and self-consistent phonons: [code]; [paper]
AlmaBTE – Boltzmann transport for device level simulations: [code]; [paper]
DynaPhoPy – Anharmonic phonons from molecular dynamics simulations: [code]; [paper]
D3q – 3-phonon processes and stochastic self-consistent phonons using random displacements: [code]; [paper]
Phono3py – 3-phonon processes and thermal conductivity from finite-displacements: [code]; [paper]
SCALID – self-consistent phonon approach, but no longer developed and fails for optic modes: [code]; [paper]
ShengBTE – 3-phonon processes and thermal conductivity from finite-displacements: [code]; [paper]
TDEP – effective Hamiltonian approach for anharmonic systems from molecular dynamics simulations: [code]; [paper]