Probability of metastable configurations in spherical three-dimensional Yukawa crystals

TL;DR

This paper investigates the probabilities of metastable versus ground states in three-dimensional Yukawa clusters, revealing that metastable states can be more probable depending on interaction parameters, using simulations and analytical methods.

Contribution

It introduces an analytical approach based on the canonical partition function to explain metastable state probabilities in Yukawa clusters, complementing simulation results.

Findings

Metastable states can have higher occurrence probabilities than ground states.

Probabilities depend strongly on the Yukawa screening parameter.

Analytical insights clarify mechanisms behind state occurrence probabilities.

Abstract

Recently the occurrence probabilities of ground- and metastable states of three-dimensional Yukawa clusters with 27 and 31 particles have been analyzed in dusty plasma experiments [Block et al., Physics of Plasmas 15, 040701 (2008)]. There it was found that, in many cases, the ground state appeared substantially less frequently than excited states. Here we analyze this question theoretically by means of molecular dynamics (MD) and Monte Carlo simulations and an analytical method based on the canonical partition function. We confirm that metastable states can occur with a significantly higher probability than the ground state. The results strongly depend on the screening parameter of the Yukawa interaction and the damping coefficient used in the MD simulations. The analytical method allows one to gain insight into the mechanisms being responsible for the occurrence probabilities of metastable states in strongly correlated finite systems.