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arXiv · 2208.14047

An excited atom interacting with a Chern insulator: towards a far-field resonant Casimir-Polder repulsion

Bing-Sui Lu·Khatee Zathul Arifa·Martial Ducloy
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Abstract

We consider the resonant Casimir-Polder interaction of an excited alkali-type atom which has a single (electric dipole) transition with a Chern insulator. The Chern insulator has a nonzero, time reversal symmetry breaking Hall conductance, leading to an additional contribution to the resonant Casimir-Polder interaction which depends on the coupling between the Hall conductance and the circular polarization state of the atomic transition. We find that the resonant Casimir-Polder shift can be significantly enhanced for de-excitation frequencies near values associated with the van Hove singularities of the Chern insulator. Furthermore, we find that the resonant Casimir-Polder force can become monotonically decaying and repulsive for a relatively large atom-surface distance, if the atomic dipole transition is right circularly polarized and the Chern number of the Chern insulator is $-1$ or the atomic dipole transition is left circularly polarized and the Chern number is $1$.

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Bing-Sui Lu, Khatee Zathul Arifa, Martial Ducloy. 2022-08-30. An excited atom interacting with a Chern insulator: towards a far-field resonant Casimir-Polder repulsion. https://doi.org/10.1140/epjd%2Fs10053-022-00544-x

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