Parallel implementation of spin and spin-lattice simulations in LAMMPS
Julien Tranchida, Aidan P. ThompsonMultiscale Science Department, Sandia National Laboratories,
Deriving from the DFT formalism, a semi-classical methodology referred to as spin dynamics (SD) can be used as a reliable tool for the simulation of the magnetization dynamics in systems containing a large number of interacting magnetic spins 1, like spin lattices 2, or spin liquids 3. More recently, it has also been shown possible to couple spin degrees of freedom to lattice vibrations by combining the formalism of molecular dynamics to spin dynamics 4, using empirical potentials 5. The goal of our project is to construct an efficient parallel implementation of SD in Sandia's widely-used LAMMPS molecular dynamics code 6. This will allow spin-lattice simulations to use parallel computers to access length and timescales much larger than currently possible. This work will leverage LAMMPS' sophisticated integration algorithms and the highly parallel structures.
Keywords: Magnetization dynamics, Spin-lattice simulations, Molecular dynamics
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