arXiv:1610.04492 · Physical review. B./Physical review. B

Nonequilibrium effects on charge and energy partitioning after an interaction quench

Alessio Calzona, Filippo Maria Gambetta, Matteo Carrega, Fabio Cavaliere, Maura Sassetti

Published Feb 1, 2017• 15 citations

Abstract

Charge and energy fractionalization are among the most intriguing features of interacting one-dimensional 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 noninteracting one-dimensional probe. Here, we demonstrate that the system settles to a steady state in which the charge fractionalization ratio is unaffected by the prequenched parameters. On the contrary, due to the postquench nonequilibrium spectral function, the energy partitioning ratio is strongly modified, reaching values larger than 1. This is a peculiar feature of the nonequilibrium dynamics of the quench process and it is in sharp contrast with the nonquenched case, where the ratio is bounded by 1.

DOI: 10.1103/physrevb.95.085101

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