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arXiv · 2506.15579

Advanced Langevin thermostats: Properties, extensions to rheology, and a lean momentum-conserving approach

Shubham Agarwal·Sergey V. Sukhomlinov·Marc Honecker·Martin H. Müser
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Abstract

The Langevin equation accounts for unresolved bath degrees of freedom driving the system toward the bath temperature. Because of this, numerical solutions of the Langevin equation have a long history. Here, we recapitulate, combine, and extend existing Langevin-equation based thermostats, scrutinize their properties and demonstrate their superiority over global kinetic-energy controls. Our work includes compact, asymptotic-analysis based derivations of stochastic thermostats, including the highly accurate Gr{\o}nbech-Jensen scheme. Proposed extensions include a precise, colored and a lean, momentum-conserving thermostat.

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Shubham Agarwal, Sergey V. Sukhomlinov, Marc Honecker, Martin H. Müser. 2025-06-18. Advanced Langevin thermostats: Properties, extensions to rheology, and a lean momentum-conserving approach. https://arxiv.org/abs/2506.15579

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