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arXiv · 1405.5541

Anomalous nonequilibrium current fluctuations in the Heisenberg model

Marko Znidaric
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Abstract

We study fluctuation properties of a one-dimensional anisotropic Heisenberg model out of equilibrium, focusing in particular on the gapped regime. Within the open-system setting we study large-deviation properties of the spin current. Numerically evaluating the first four current cumulants in a nonequilibrium stationary state at high energies, we find that the first two cumulants scale with the system size in a diffusive way, while the 3rd and the 4th cumulants do not. This means that the model is not an ordinary diffusive spin conductor.

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Marko Znidaric. 2014-05-21. Anomalous nonequilibrium current fluctuations in the Heisenberg model. https://doi.org/10.1103/physrevb.90.115156

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