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arXiv · 2011.03753

Photon Condensation and Enhanced Magnetism in Cavity QED

Juan Román-Roche·Fernando Luis·David Zueco
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Abstract

A system of magnetic molecules coupled to microwave cavities ($LC$ resonators) undergoes the equilibrium superradiant phase transition. The transition is experimentally observable. The effect of the coupling is first illustrated by the vacuum-induced ferromagnetic order in a quantum Ising model and then by the modification of the magnetic phase diagram of ${\rm Fe_8}$ dipolar crystals, exemplifying the cooperation between intrinsic and photon-induced spin-spin interactions. Finally, a transmission experiment is shown to resolve the transition, measuring the quantum electrodynamical control of magnetism.

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Juan Román-Roche, Fernando Luis, David Zueco. 2020-11-07. Photon Condensation and Enhanced Magnetism in Cavity QED. https://doi.org/10.1103/physrevlett.127.167201

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