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arXiv · 2408.03693

A molecular dynamics framework coupled with smoothed particle hydrodynamics for quantum plasma simulations

Thomas Campbell·Pontus Svensson·Brett Larder·Daniel Plummer·Sam M. Vinko·Gianluca Gregori
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Abstract

We present a novel scheme for modelling quantum plasmas in the warm dense matter (WDM) regime via a hybrid smoothed particle hydrodynamic - molecular dynamic treatment, here referred to as 'Bohm SPH'. This treatment is founded upon Bohm's interpretation of quantum mechanics for partially degenerate fluids, does not apply the Born-Oppenheimer approximation, and is computationally tractable, capable of modelling dynamics over ionic timescales at electronic time resolution. Bohm SPH is also capable of modelling non-Gaussian electron wavefunctions. We present an overview of our methodology, validation tests of the single particle case including the hydrogen 1s wavefunction, and comparisons to simulations of a warm dense hydrogen system performed with wave packet molecular dynamics.

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Thomas Campbell, Pontus Svensson, Brett Larder, Daniel Plummer, Sam M. Vinko, Gianluca Gregori. 2024-08-07. A molecular dynamics framework coupled with smoothed particle hydrodynamics for quantum plasma simulations. https://arxiv.org/abs/2408.03693

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