Tomaz Prosen

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The anisotropic Heisenberg chain of spins 1/2 is one of the key paradigms of strongly
correlated electrons in one dimension. While equilibrium properties of the model
are relatively well understood, even very basic questions about its non-equilibrium
properties were still open until very recently. A prominent example is the question
whether the model exhibits ballistic spin transport at finite temperatures or not?
I will outline the progress on this topic which has been triggered by the discovery
of exact solution of quantum master equation of the boundary driven Heisenberg
chain. The steady-state solution of non-equilibrium master equation leads
to novel quasi-local conservation laws, which in turn lead to a derivation
of rigorous strict lower bounds on ballistic transport coefficients. I will also
explain how such an approach of `non-equilibrium integrability' works for some other
strongly interacting quantum chains, for instance, for the Hubbard model or Lai-
Sutherland model of spins 1.

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University of Ljubljana
Seminar Room TP 0.03
Contact: Vladislav Popkov