Confined Quantum Hard Spheres

Entropy (Basel). 2021 Jun 18;23(6):775. doi: 10.3390/e23060775.

Abstract

We present computer simulation and theoretical results for a system of N Quantum Hard Spheres (QHS) particles of diameter σ and mass m at temperature T, confined between parallel hard walls separated by a distance Hσ, within the range 1≤H≤∞. Semiclassical Monte Carlo computer simulations were performed adapted to a confined space, considering effects in terms of the density of particles ρ*=N/V, where V is the accessible volume, the inverse length H-1 and the de Broglie's thermal wavelength λB=h/2πmkT, where k and h are the Boltzmann's and Planck's constants, respectively. For the case of extreme and maximum confinement, 0.5<H-1<1 and H-1=1, respectively, analytical results can be given based on an extension for quantum systems of the Helmholtz free energies for the corresponding classical systems.

Keywords: hard spheres; perturbation theory; quantum Monte Carlo; quantum fluids.