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arXiv · 0903.0895

Quantum Quench from a Thermal Initial State

Spyros Sotiriadis·Pasquale Calabrese·John Cardy
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Abstract

We consider a quantum quench in a system of free bosons, starting from a thermal initial state. As in the case where the system is initially in the ground state, any finite subsystem eventually reaches a stationary thermal state with a momentum-dependent effective temperature. We find that this can, in some cases, even be lower than the initial temperature. We also study lattice effects and discuss more general types of quenches.

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Spyros Sotiriadis, Pasquale Calabrese, John Cardy. 2009-07-30. Quantum Quench from a Thermal Initial State. https://doi.org/10.1209/0295-5075/87/20002

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