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arXiv · 0810.5508

Effective thermal dynamics following a quantum quench in a spin chain

Davide Rossini·Alessandro Silva·Giuseppe Mussardo·Giuseppe Santoro
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Abstract

We study the nonequilibrium dynamics of the Quantum Ising Model following an abrupt quench of the transverse field. We focus on the on-site autocorrelation function of the order parameter, and extract the phase coherence time $τ^ϕ_Q$ from its asymptotic behavior. We show that the initial state determines $τ^ϕ_Q$ only through an effective temperature set by its energy and the final Hamiltonian. Moreover, we observe that the dependence of $τ^ϕ_Q$ on the effective temperature fairly agrees with that obtained in thermal equilibrium as a function of the equilibrium temperature.

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Davide Rossini, Alessandro Silva, Giuseppe Mussardo, Giuseppe Santoro. 2009-03-27. Effective thermal dynamics following a quantum quench in a spin chain. https://doi.org/10.1103/physrevlett.102.127204

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