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arXiv · 1704.01731

Origin of Temperature Gradient in Nonequilibrium Steady States in Weakly Coupled Quantum Spin Systems

Toyohiko Ishida·Ayumu Sugita
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Abstract

We study nonequilibrium steady states (NESSs) in quantum spin-1/2 chains in contact with two heat baths at different temperatures. We consider the weak-coupling limit both for spin-spin coupling in the system and for system-bath coupling. This setting allows us to treat NESSs with a nonzero temperature gradient analytically. We develop a perturbation theory for this weak-coupling situation and show a simple condition for the existence of nonzero temperature gradient. This condition is independent of the integrability of the system.

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Toyohiko Ishida, Ayumu Sugita. 2017-04-06. Origin of Temperature Gradient in Nonequilibrium Steady States in Weakly Coupled Quantum Spin Systems. https://doi.org/10.7566/jpsj.85.074006

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