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arXiv · 1104.0154

Quantum Quench in the Transverse Field Ising Chain

Pasquale Calabrese·Fabian H. L. Essler·Maurizio Fagotti
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Abstract

We consider the time evolution of observables in the transverse field Ising chain (TFIC) after a sudden quench of the magnetic field. We provide exact analytical results for the asymptotic time and distance dependence of one- and two-point correlation functions of the order parameter. We employ two complementary approaches based on asymptotic evaluations of determinants and form-factor sums. We prove that the stationary value of the two-point correlation function is not thermal, but can be described by a generalized Gibbs ensemble (GGE). The approach to the stationary state can also be understood in terms of a GGE. We present a conjecture on how these results generalize to particular quenches in other integrable models.

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Pasquale Calabrese, Fabian H. L. Essler, Maurizio Fagotti. 2011-04-01. Quantum Quench in the Transverse Field Ising Chain. https://doi.org/10.1103/physrevlett.106.227203

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