Auto-correlations of Microscopic Density Fluctuations for Yukawa Fluids in the Generalized Hydrodynamics Framework

TL;DR

This paper develops an analytical method within the generalized hydrodynamics framework to derive transport coefficients of Yukawa fluids from density fluctuations, validated against molecular dynamics simulations of dusty plasmas.

Contribution

It introduces an exact hydrodynamic matrix approach to analytically compute the density autocorrelation function for strongly coupled Yukawa systems, incorporating visco-elastic effects.

Findings

Analytic expressions for the density autocorrelation function are derived.

Transport coefficients are obtained and compared with existing literature.

The method is validated against molecular dynamics simulation data.

Abstract

The present work develops a theoretical procedure for obtaining transport coefficients of Yukawa systems from density fluctuations. The dynamics of Yukawa systems are described in the framework of the generalized hydrodynamic model that incorporates strong coupling and visco-elastic memory effects. A hydrodynamic matrix for such a system is exactly derived and then used to obtain an analytic expression for the density autocorrelation function (DAF)- a marker of the time dynamics of density fluctuations. The present approach is validated against a DAF obtained from numerical data of Molecular Dynamics (MD) simulations of a dusty plasma system that is a practical example of a Yukawa system. The MD results and analytic expressions derived from the model equations are then used to obtain various transport coefficients and the latter are compared with values available in the literature from other models. The influence of strong coupling and visco-elastic effects on the transport parameters are discussed. Finally, the utility of our calculations for obtaining reliable estimates of transport coefficients from experimentally determined DAF is pointed out.