2011/03/31 by Tomaz Prosen · 2 citations
Physics and Astronomy · #cond-mat.str-el #cond-mat.stat-mech #nlin.SI #quant-ph
paper · pdf · doi:10.1103/physrevlett.106.217206
published as Phys. Rev. Lett. 106, 217206 (2011) · Slightly longer but essentially equivalent to a published version
arxiv created 2011/05/27 · arxiv updated 2011/05/30
Explicit matrix product ansatz is presented, in first two orders in the (weak) coupling parameter, for the non-equilibrium steady state of the homogeneous, nearest neighbor Heisenberg XXZ spin-1/2 chain driven by Lindblad operators which act only at the edges of the chain. The first order of the density operator becomes in thermodynamic limit an exact pseudo-local conservation law and yields -- via Mazur inequality -- a rigorous lower bound on the high temperature spin Drude weight. Such Mazur bound is a non-vanishing fractal function of the anisotropy parameter Delta for |Delta|<1.