Molecular dynamics investigations on a quantum system in a thermostat

TL;DR

This paper explores a molecular dynamics approach to simulate a quantum fermionic system in a harmonic potential at constant temperature, introducing a novel thermostat mechanism that mimics quantum thermal behavior.

Contribution

It presents a new method coupling an auxiliary degree of freedom as a thermometer to control temperature in quantum molecular dynamics simulations.

Findings

The method effectively maintains target temperature in quantum fermionic systems.

The approach demonstrates potential for simulating quantum systems with classical-like thermostats.

It highlights differences between quantum and classical equipartition in simulation contexts.

Abstract

The model quantum system of fermions in a one dimensional harmonic oscillator potential is investigated by a molecular dynamics method at constant temperature. Although in quantum mechanics the equipartition theorem cannot be used like in the Nose-Hoover-thermostat it is possible to couple an additional degree of freedom to the system which acts as a thermometer and drives the system towards the desired temperature via complex time steps.