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arXiv · 1609.06483

Finite speed heat transport in a quantum spin chain after quenched local cooling

Pascal Fries·Haye Hinrichsen
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Abstract

We study the dynamics of an initially thermalized spin chain in the quantum XY-model, after sudden coupling to a heat bath of lower temperature at one end of the chain. In the semi-classical limit we see an exponential decay of the system-bath heatflux by exact solution of the reduced dynamics. In the full quantum description however, we numerically find the heatflux to reach intermediate plateaus where it is approximately constant -- a phenomenon that we attribute to the finite speed of heat transport via spin waves.

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Pascal Fries, Haye Hinrichsen. 2016-09-21. Finite speed heat transport in a quantum spin chain after quenched local cooling. https://doi.org/10.1088/1751-8121%2Faa617a

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