Transport in a one-dimensional isotropic Heisenberg model at high temperature
arXiv:1112.2551 · doi:10.1088/1742-5468/2011/12/P12008
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.
12 pages, 6 figures