Repulsive Casimir forces between solid materials with high refractive index intervening liquids

TL;DR

This paper develops a method to accurately predict repulsive Casimir forces between solid materials with high refractive index liquids as intervening media, using dielectric data and Kramers-Kronig consistency.

Contribution

It introduces a scheme based on dielectric constants and refractive indices, applying KK consistency to improve force calculations via Lifshitz theory.

Findings

Provides a reliable method for predicting repulsive Casimir forces.

Analyzes dielectric data for various materials and liquids.

Enhances accuracy of force calculations using KK consistency.

Abstract

In order to explore repulsive Casimir/van der Waals forces between solid materials with liquid as the intervening medium, we analyze dielectric data for a wide range of materials as for example PTFE, polystyrene, silica and more than twenty liquids. Although significant variation in the dielectric data from different sources exist, we provide a scheme based on measured static dielectric constants, refractive indices, and applying Kramers Kronig (KK) consistency to dielectric data to create accurate dielectric functions at imaginary frequencies. The latter is necessary for more accurate force calculations via the Lifshitz theory allowing reliable predictions of repulsive Casimir forces.