Density of states of a 2D system of soft--sphere fermions by path integral Monte Carlo simulations

V. Filinov; P. Levashov; A. Larkin

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arXiv · 2305.07601

Density of states of a 2D system of soft--sphere fermions by path integral Monte Carlo simulations

V. Filinov·P. Levashov·A. Larkin

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Abstract

The Wigner formulation of quantum mechanics is used to derive a new path integral representation of quantum density of states. A path integral Monte Carlo approach is developed for the numerical investigation of density of states, internal energy and spin--resolved radial distribution functions for a 2D system of strongly correlated soft--sphere fermions. The peculiarities of the density of states and internal energy distributions depending on the hardness of the soft--sphere potential and particle density are investigated and explained. In particular, at high enough densities the density of states rapidly tends to a constant value, as for an ideal system of 2D fermions.

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V. Filinov, P. Levashov, A. Larkin. 2023-05-12. Density of states of a 2D system of soft--sphere fermions by path integral Monte Carlo simulations. https://arxiv.org/abs/2305.07601

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