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arXiv · 2503.13955

Nonresonant Casimir-Polder repulsion with a monolayer topological insulator

Bing-Sui Lu
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Abstract

We investigate the behavior of the nonresonant Casimir-Polder force acting on a metastable polarized state of a two-level atomic system with a right-circularly polarized electric dipole transition in the presence of a monolayer topological insulator inhabiting an anomalous quantum Hall insulator state with a negative Chern number, finding that the force can be repulsive for a certain range within the far-field region. By considering stanene irradiated by circularly polarized monochromatic laser light as a material example of a monolayer topological insulator, we study the effect of the frequency dispersion in the conductivity tensor on the force behavior, finding that the dispersion generally leads to a slight downward shift of the force relative to that predicted by a nondispersive approximation, as well as a slight reduction of the range over which the force is repulsive.

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Bing-Sui Lu. 2025-05-03. Nonresonant Casimir-Polder repulsion with a monolayer topological insulator. https://doi.org/10.1209/0295-5075%2Fadd36e

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