Simulating electronic-temperature effects in warm dense aluminium
Tom Yates, CMTH Group
Simulating warm dense matter requires equal consideration of both quantum and thermal effects. The commonly used methods are often limited by the poor scaling of computational and time requirements with electronic temperature. In this talk, I first compare two of the currently available DFT methods for calculating interatomic forces in the warm dense regime. I will then show that an atomic cluster expansion (ACE) fit to finite-temperature DFT data can provide accurate forces in warm dense aluminium at a fraction of the cost of ab initio methods. The ACE potentials work well over a wide range of densities, and the use of a simple linear interpolation scheme allows us to accurately probe intermediate electronic temperatures. Finally, I will discuss potential applications of the finite-temperature ACE potentials in molecular dynamics simulations of experimentally realisable systems.