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arXiv · 1103.4094

Spin transport in a one-dimensional anisotropic Heisenberg model

Marko Znidaric
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Abstract

We analytically and numerically study spin transport in a one-dimensional Heisenberg model in linear-response regime at infinite temperature. It is shown that as the anisotropy parameter Delta is varied spin transport changes from ballistic for Delta<1 to anomalous at the isotropic point Delta=1, to diffusive for finite Delta>1, ending up as a perfect isolator in the Ising limit of infinite Delta. Using perturbation theory for large Delta a quantitative prediction is made for the dependence of diffusion constant on Delta.

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Marko Znidaric. 2011-06-02. Spin transport in a one-dimensional anisotropic Heisenberg model. https://doi.org/10.1103/physrevlett.106.220601

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