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

TL;DR

This paper investigates magnetization transport in a high-temperature one-dimensional isotropic Heisenberg model, revealing anomalous diffusion characterized by a current scaling as 1/L^{0.5} and a diverging diffusion constant.

Contribution

It provides new insights into the transport properties and spectral relaxation behavior of the isotropic Heisenberg model at high temperatures.

Findings

Magnetization current scales as 1/L^{0.5} at high temperature.

Diffusion constant diverges as L^{0.5}.

Spectral properties of the relaxation superoperator are analyzed.

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.