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arXiv · 2401.14738

Switching the sign of the Casimir force between two PEMC spheres

Tanja Schoger·Gert-Ludwig Ingold
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Abstract

For non-reciprocal objects in vacuum, the Casimir interaction can become repulsive. Here, we present a comprehensive study for idealized non-reciprocal materials known as perfect electromagnetic conductors (PEMC). The system consists of two spheres made of different PEMC materials, including the plane-sphere geometry as a particular case. The sign of the Casimir force does not only depend on the distance between the spheres and their geometric parameters but can be controlled by adjusting the temperature. A repulsive Casimir interaction at small distances allows for stable equilibrium configurations of the spheres. A sum rule previously derived for the plane-plane geometry at zero temperature is violated in general, if at least one plane is replaced by a sphere.

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Tanja Schoger, Gert-Ludwig Ingold. 2024-01-26. Switching the sign of the Casimir force between two PEMC spheres. https://doi.org/10.1103/physreva.109.052815

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