Molecular Dynamics Simulations of Self Diffusion and Ion-Electron Temperature Relaxation in Strongly Magnetized Plasmas

Molecular dynamics (MD) simulations are used to study the transport properties, namely self diffusion and ion-electron temperature relaxation rates, of strongly magnetized plasmas, which are characterized by having a gyrofrequency greater than the plasma frequency. Charged particles in strongly magnetized plasmas have motion constrained to cylinders characterized by their gyroradius and collisional mean free path, leading to increased temporal and spatial correlations associated with the Coulomb collisions [1]. In order to capture this effect, the simulation domain is elongated in the direction of the magnetic field, to investigate the self diffusion in a one-component plasma. The simulation domain length required to resolve these correlations increases with increasing magnetization strength. Further, first-principles molecular dynamics simulation is used to test a recent theoretical prediction [2] that the strong magnetization causes the ion-electron temperature relaxation rates to differ in the parallel and perpendicular directions, causing a temperature anisotropy to develop. Parallel and perpendicular temperature relaxation rates for various magnetization and Coulomb coupling strengths are obtained using MD simulations and compared with the theoretical predictions.

[1] K. R. Vidal and S. D. Baalrud, Phys. Plasmas 28, 042103 (2021)

[2] L. Jose and S. D. Baalrud, Phys. Plasmas 30, 052103 (2023)