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arXiv · 2310.05277

Comparison of different thermostats in the Holstein model

N. Fialko·M. Olshevets·V. D. Lakhno
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Abstract

When modeling charge dynamics in a chain of N sites at a temperature T, a Langevin thermostat and a Hamiltonian system, i.e., a chain heated to a given temperature before charge is injected, are compared. It is shown that the polaron disruption occurs in the same range of values of the thermal energy NT, however, T is not given by the initial data, but obtained after simulation from the average kinetic energy. For large T, the results averaged over a set of trajectories in a system with a Langevin thermostat and the results averaged over time for a Hamiltonian system are close, which does not contradict the Ergodic hypothesis.

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N. Fialko, M. Olshevets, V. D. Lakhno. 2023-10-08. Comparison of different thermostats in the Holstein model. https://arxiv.org/abs/2310.05277

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