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Strong Evidence of Normal Heat Conduction in a one-Dimensional Quantum System

Keiji Saito
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Abstract

We investigate how the normal energy transport is realized in one-dimensional quantum systems using a quantum spin system. The direct investigation of local energy distribution under thermal gradient is made using the quantum master equation, and the mixing properties and the convergence of the Green-Kubo formula are investigated when the number of spin increases. We find that the autocorrelation function in the Green-Kubo formula decays as $\sim t^{-1.5}$ to a finite value which vanishes rapidly with the increase of the system size. As a result, the Green-Kubo formula converges to a finite value in the thermodynamic limit. These facts strongly support the realization of Fourier heat law in a quantum system.

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Keiji Saito. 2002-12-11. Strong Evidence of Normal Heat Conduction in a one-Dimensional Quantum System. https://doi.org/10.1209/epl%2Fi2003-00241-3

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