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arXiv · 2103.00011

Error-correction properties of an interacting topological insulator

Amit Jamadagni·Hendrik Weimer
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Abstract

We analyze the phase diagram of a topological insulator model including antiferromagnetic interactions in the form of an extended Su-Schrieffer Heeger model. To this end, we employ a recently introduced operational definition of topological order based on the ability of a system to perform topological error correction. We show that the necessary error correction statistics can be obtained efficiently using a Monte-Carlo sampling of a matrix product state representation of the ground state wave function. Specifically, we identify two distinct symmetry-protected topological phases corresponding to two different fully dimerized reference states. Finally, we extend the notion of error correction to classify thermodynamic phases to those exhibiting local order parameters, finding a topologically trivial antiferromagnetic phase for sufficiently strong interactions.

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Amit Jamadagni, Hendrik Weimer. 2021-02-26. Error-correction properties of an interacting topological insulator. https://doi.org/10.1103/physrevb.106.115133

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