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  • Letter
  • Open Access

Emergence of X states in a quantum impurity model

Moallison F. Cavalcante1,2,3,*, Marcus V. S. Bonança3, Eduardo Miranda3, and Sebastian Deffner1,2,4

  • *Contact author: moallison@umbc.edu
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Phys. Rev. Research 7, L022027 – Published 2 May, 2025

DOI: https://doi.org/10.1103/PhysRevResearch.7.L022027

Abstract

In the present work, we demonstrate the emergence of X states in the long-time response of a locally perturbed many-body quantum impurity model. The emergence of the double-qubit state is heralded by the lack of decay of the response function as well as the out-of-time order correlator, signifying the trapping of excitations and hence information in edge modes. Surprisingly, after carrying out a quantum information theory characterization, we show that such states exhibit genuine quantum correlations.

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Phys. Rev. Research 7, L022027– Published 2 May, 2025
  • Received 27 January 2025
  • Accepted 15 April 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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