Emergence of $X$ states in a quantum impurity model

TL;DR

This paper demonstrates the emergence of $X$ states in a quantum impurity model, showing long-time quantum correlations and excitation trapping, with implications for quantum information storage.

Contribution

It reveals the formation of $X$ states in a many-body quantum impurity model and characterizes their quantum correlations, a novel insight into impurity dynamics.

Findings

$X$ states emerge in long-time response of the model.

Response function and out-of-time correlator do not decay.

$X$ states exhibit genuine quantum correlations.

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.