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arXiv · 2501.13914

Emergence of $X$ states in a quantum impurity model

Moallison F. Cavalcante·Marcus V. S. Bonança·Eduardo Miranda·Sebastian Deffner
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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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Moallison F. Cavalcante, Marcus V. S. Bonança, Eduardo Miranda, Sebastian Deffner. 2025-01-23. Emergence of $X$ states in a quantum impurity model. https://doi.org/10.1103/physrevresearch.7.l022027

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