Single-Interface Casimir Torque

TL;DR

This paper demonstrates that quantum electromagnetic fluctuations induce a torque at the interface of anisotropic materials, which depends on interface zero-point energy and influences the system's equilibrium positions.

Contribution

It introduces a theory showing that single-interface Casimir torque depends on interface zero-point energy and is crucial for understanding anisotropic Casimir physics.

Findings

Torque depends on interface zero-point energy.

Single-interface torque influences equilibrium positions.

Theory applies to anisotropic and isotropic material interfaces.

Abstract

It is shown that the quantum fluctuations of the electromagnetic field generally induce a torque at the interface of an anisotropic material with another anisotropic or isotropic material. It is proven that this torque depends on an interface zero-point energy determined by the dispersion of the interface (localized and extended) modes. Our theory demonstrates that the single-interface torque is essential to understand the Casimir physics of material systems with anisotropic elements and determines the equilibrium positions of the system.