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arXiv · 2307.02524

Large Deviations Beyond the Kibble-Zurek Mechanism

Federico Balducci·Mathieu Beau·Jing Yang·Andrea Gambassi·Adolfo del Campo
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Abstract

The Kibble-Zurek mechanism (KZM) predicts that the average number of topological defects generated upon crossing a continuous or quantum phase transition obeys a universal scaling law with the quench time. Fluctuations in the defect number near equilibrium are approximately of Gaussian form, in agreement with the central limit theorem. Using large deviations theory, we characterize the universality of fluctuations beyond the KZM and report the exact form of the rate function in the transverse-field quantum Ising model. In addition, we characterize the scaling of large deviations in an arbitrary continuous phase transition, building on recent evidence establishing the universality of the defect number distribution.

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Federico Balducci, Mathieu Beau, Jing Yang, Andrea Gambassi, Adolfo del Campo. 2023-07-05. Large Deviations Beyond the Kibble-Zurek Mechanism. https://doi.org/10.1103/physrevlett.131.230401

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