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arXiv · 2410.00682

Relaxation dynamics of integrable field theories after a global quantum quench

Emanuele Di Salvo·Dirk Schuricht
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Abstract

We apply the linked cluster expansion as well as the quench action approach to study the time evolution of one-point functions after a quantum quench in integrable field theories. We argue that the relaxation towards the stationary value fundamentally differs depending on the locality properties of the considered observable: while for local operators both exponential and power-law decaying terms are present in the dynamics, for semi-local operators the latter are absent. We explicitly confirm this for the Ising field theory, the sinh-Gordon model, and the repulsive sine-Gordon model.

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Emanuele Di Salvo, Dirk Schuricht. 2024-10-01. Relaxation dynamics of integrable field theories after a global quantum quench. https://doi.org/10.1088/1742-5468/ad9f4e

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