title: Determination of the Nonequilibrium Steady State Emerging from a Defect.
abstract: We consider the nonequilibrium 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.
authors.affiliation: SISSA and INFN, via Bonomea 265, 34136 Trieste, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Bertini
authors.affiliation: Département de Physique, École Normale Supérieure / PSL Research University, CNRS, 24 rue Lhomond, 75005 Paris, France.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Fagotti