Repulsive and attractive Casimir interactions in liquids

TL;DR

This paper investigates the Casimir forces in solid-liquid-solid systems using Lifshitz theory, revealing both repulsive and attractive interactions depending on material combinations and separation distances.

Contribution

It provides a detailed analysis of Casimir interactions in liquid environments for various material pairs, including stable configurations and force nature.

Findings

Casimir forces can be both repulsive and attractive between gold and silica or MgO.

Stable system configurations are identified based on force analysis.

The study offers guidance for future experimental exploration of dispersion interactions.

Abstract

The Casimir interactions in the solid-liquid-solid systems as a function of separation distance have been studied by the Lifshitz theory. The dielectric permittivity functions for a wide range of materials are described by Drude, Drude-Lorentz and oscillator models. We find that the Casimir forces between gold and silica or MgO materials are both the repulsive and attractive. We also find the stable forms for the systems. Our studies would provide a good guidance for the future experimental studies on the dispersion interactions.