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arXiv · 2008.02285

Topological and symmetry-enriched random quantum critical points

Carlos M. Duque·Hong-Ye Hu·Yi-Zhuang You·Vedika Khemani·Ruben Verresen·Romain Vasseur
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Abstract

We study how symmetry can enrich strong-randomness quantum critical points and phases, and lead to robust topological edge modes coexisting with critical bulk fluctuations. These are the disordered analogues of gapless topological phases. Using real-space and density matrix renormalization group approaches, we analyze the boundary and bulk critical behavior of such symmetry-enriched random quantum spin chains. We uncover a new class of symmetry-enriched infinite randomness fixed points: while local bulk properties are indistinguishable from conventional random singlet phases, nonlocal observables and boundary critical behavior are controlled by a different renormalization group fixed point. We also illustrate how such new quantum critical points emerge naturally in Floquet systems.

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cond-mat.str-elcond-mat.dis-nncond-mat.stat-mechquant-ph

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Carlos M. Duque, Hong-Ye Hu, Yi-Zhuang You, Vedika Khemani, Ruben Verresen, Romain Vasseur. 2020-08-05. Topological and symmetry-enriched random quantum critical points. https://doi.org/10.1103/physrevb.103.l100207

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