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arXiv · 2507.01486

Exactly Solvable Phase Transition in a Cavity-Coupled 1D Ising Chain

Shuntaro Otake·Motoaki Bamba
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Abstract

Although one-dimensional classical spin chains do not exhibit phase transitions, we found that a phase transition does occur when they are coupled to a cavity photon mode. This provides the simplest exactly solvable examples demonstrating that finite-temperature superradiant phase transitions can emerge from long-range fully connected interactions mediated by photons and interactions within the material.

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Shuntaro Otake, Motoaki Bamba. 2025-07-02. Exactly Solvable Phase Transition in a Cavity-Coupled 1D Ising Chain. https://doi.org/10.1103/fxml-nv46

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