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arXiv · 1409.8482

Stationary states in a free fermionic chain from the Quench Action Method

Andrea De Luca·Gabriele Martelloni·Jacopo Viti
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Abstract

We employ the Quench Action Method (QAM) for a recently considered geometrical quantum quench: two free fermionic chains initially at different temperatures are joined together in the middle and let evolve unitarily with a translation invariant Hamiltonian. We show that two different stationary regimes are reached at long times, depending on the interplay between the observation time scale T and the total length L of the system. We show the emergence of a non-equilibrium steady state (NESS) supporting an energy current for observation time T much smaller than the system size L. We then identify a longer time-scale for which thermalization occurs in a Generalized Gibbs Ensemble (GGE).

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Andrea De Luca, Gabriele Martelloni, Jacopo Viti. 2014-09-30. Stationary states in a free fermionic chain from the Quench Action Method. https://doi.org/10.1103/physreva.91.021603

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