Shear viscosity of two-dimensional Yukawa systems in liquid state

TL;DR

This study uses molecular dynamics simulations to analyze the shear viscosity of 2D Yukawa systems, revealing a viscosity minimum at a specific coupling and contrasting decay behaviors with previous work, relevant for condensed matter and plasma physics.

Contribution

First comprehensive molecular dynamics analysis of shear viscosity in 2D Yukawa liquids, highlighting a viscosity minimum and decay characteristics distinct from earlier studies.

Findings

Viscosity exhibits a minimum at Coulomb coupling ~17.

Stress autocorrelation decays rapidly, differing from prior reports.

Results align with recent dusty plasma experiments.

Abstract

The shear viscosity of a two-dimensional (2D) liquid was calculated using equilibrium molecular dynamics simulations with a Yukawa potential. The shear viscosity has a minimum, at a Coulomb coupling parameter of about 17, arising from the temperature dependence of the kinetic and potential contributions. Previous calculations of 2D viscosity were less extensive, and for a different potential. The stress autocorrelation function was found to decay rapidly, contrary to some earlier work. These results are useful for 2D condensed matter systems and are compared to a recent dusty plasma experiment.