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arXiv · 2302.09964

Photon condensation, Van Vleck paramagnetism, and chiral cavities

Alberto Mercurio·Gian Marcello Andolina·Francesco M. D. Pellegrino·Omar Di Stefano·Pablo Jarillo-Herrero·Claudia Felser·Frank H. L. Koppens·Salvatore Savasta·Marco Polini
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Abstract

We introduce a gauge-invariant model of planar, square molecules coupled to a quantized spatially-varying cavity electromagnetic vector potential A(r). Specifically, we choose a temporally chiral cavity hosting a uniform magnetic field B, as this is the simplest instance in which a transverse spatially-varying A(r) is at play. We show that when the molecules are in the Van Vleck paramagnetic regime, an equilibrium quantum phase transition to a photon condensate state occurs.

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Alberto Mercurio, Gian Marcello Andolina, Francesco M. D. Pellegrino, Omar Di Stefano, Pablo Jarillo-Herrero, Claudia Felser, Frank H. L. Koppens, Salvatore Savasta, Marco Polini. 2023-02-20. Photon condensation, Van Vleck paramagnetism, and chiral cavities. https://doi.org/10.1103/physrevresearch.6.013303

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