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arXiv · 1604.04276

Determination of the Nonequilibrium Steady State Emerging from a Defect

Bruno Bertini·Maurizio Fagotti
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Abstract

We consider the non-equilibrium time evolution of a translationally invariant state under a Hamiltonian with a localized defect. We discern the situations where a light-cone spreads out from the defect and separates the system into regions with macroscopically different properties. We identify the light-cone and propose a procedure to obtain a (quasi-)stationary state describing the late time dynamics of local observables. As an explicit example, we study the time evolution generated by the Hamiltonian of the transverse-field Ising chain with a local defect that cuts the interaction between two sites (a quench of the boundary conditions alongside a global quench). We solve the dynamics exactly and show that the late time properties can be obtained with the general method proposed.

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BibTeXRIS

Bruno Bertini, Maurizio Fagotti. 2016-09-23. Determination of the Nonequilibrium Steady State Emerging from a Defect. https://doi.org/10.1103/physrevlett.117.130402

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