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arXiv · 2312.13372

Nonequilibrium Criticality at the Onset of Time-Crystalline Order

Abstract

We explore the phase transitions at the onset of time-crystalline order in $O(N)$ models driven out-of-equilibrium. The spontaneous breaking of time translation symmetry and its Goldstone mode are captured by an effective description with $O(N)\times SO(2)$ symmetry. Using the renormalization group and the $\epsilon=4-d$ expansion in a leading two-loop analysis, we identify a new non-equilibrium universality class. Strikingly, it controls the long-distance physics no matter how small the microscopic breaking of equilibrium conditions is. The $O(N=2)\times SO(2)$ symmetry group is realized for magnon condensation in pumped yttirum iron garnet (YIG) films and in exciton-polariton systems with a polarization degree of freedom.

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BibTeXRIS

Romain Daviet, Carl Philipp Zelle, Achim Rosch, Sebastian Diehl. 2023-12-20. Nonequilibrium Criticality at the Onset of Time-Crystalline Order. https://doi.org/10.1103/physrevlett.132.167102

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