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arXiv · 1610.04492

Non-equilibrium effects on charge and energy partitioning after an interaction quench

Abstract

Charge and energy fractionalization are among the most intriguing features of interacting onedimensional fermion systems. In this work we determine how these phenomena are modified in the presence of an interaction quench. Charge and energy are injected into the system suddenly after the quench, by means of tunneling processes with a non-interacting one-dimensional probe. Here, we demonstrate that the system settles to a steady state in which the charge fractionalization ratio is unaffected by the pre-quenched parameters. On the contrary, due to the post-quench nonequilibrium spectral function, the energy partitioning ratio is strongly modified, reaching values larger than one. This is a peculiar feature of the non-equilibrium dynamics of the quench process and it is in sharp contrast with the non-quenched case, where the ratio is bounded by one.

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Alessio Calzona, Filippo Maria Gambetta, Matteo Carrega, Fabio Cavaliere, Maura Sassetti. 2016-12-13. Non-equilibrium effects on charge and energy partitioning after an interaction quench. https://doi.org/10.1103/physrevb.95.085101

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