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arXiv · 2102.00307

Negative-temperature Fourier transport in one-dimensional systems

Marco Baldovin·Stefano Iubini
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Abstract

We investigate nonequilibrium steady states in a class of one-dimensional diffusive systems that can attain negative absolute temperatures. The cases of a paramagnetic spin system, a Hamiltonian rotator chain and a one-dimensional discrete linear Schrödinger equation are considered. Suitable models of reservoirs are implemented to impose given, possibly negative, temperatures at the chain ends. We show that a phenomenological description in terms of a Fourier law can consistently describe unusual transport regimes where the temperature profiles are entirely or partially in the negative-temperature region. Negative-temperature Fourier transport is observed both for deterministic and stochastic dynamics and it can be generalized to coupled transport when two or more thermodynamic currents flow through the system.

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Marco Baldovin, Stefano Iubini. 2021-05-25. Negative-temperature Fourier transport in one-dimensional systems. https://doi.org/10.1088/1742-5468%2Fabf7bd

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