2015/07/31 by Enej Ilievski, Jacopo De Nardis, Bram Wouters +3 · 1 citation
Physics and Astronomy · #quant-ph #cond-mat.stat-mech #cond-mat.str-el
paper · pdf · doi:10.1103/physrevlett.115.157201
published as Phys. Rev. Lett. 115, 157201 (2015) · 5 + 3 pages, 1 figure, RevTex; v2 (minor revision)
arxiv created 2015/08/25 · arxiv updated 2015/10/14
In integrable many-particle systems, it is widely believed that the stationary state reached at late times after a quantum quench can be described by a generalized Gibbs ensemble (GGE) constructed from their extensive number of conserved charges. A crucial issue is then to identify a complete set of these charges, enabling the GGE to provide exact steady state predictions. Here we solve this long-standing problem for the case of the spin-1/2 Heisenberg chain by explicitly constructing a GGE which uniquely fixes the macrostate describing the stationary behaviour after a general quantum quench. A crucial ingredient in our method, which readily generalizes to other integrable models, are recently discovered quasi-local charges. As a test, we reproduce the exact post-quench steady state of the Neel quench problem obtained previously by means of the Quench Action method.