Transport in a one-dimensional isotropic Heisenberg model at high temperature

Marko Znidaric

doi:10.1088/1742-5468/2011/12/p12008

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arXiv · 1112.2551

Transport in a one-dimensional isotropic Heisenberg model at high temperature

Marko Znidaric

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Abstract

Magnetization transport in a one-dimensional isotropic spin 1/2 Heisenberg model is studied. It is shown that in a nonequilibrium steady state at high temperature and constant small driving the magnetization current depends on the system length L as 1/L^{0.5}, meaning that the diffusion constant diverges as L^{0.5}. Spectral properties of a superoperator governing the relaxation towards a nonequilibrium steady state are also discussed.

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Marko Znidaric. 2011-12-12. Transport in a one-dimensional isotropic Heisenberg model at high temperature. https://doi.org/10.1088/1742-5468%2F2011%2F12%2Fp12008

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