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DOE OSTI · 1773419

Topological and symmetry-enriched random quantum critical points

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

In this work, 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 analogs 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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74 ATOMIC AND MOLECULAR PHYSICS75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

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Duque, Carlos M., Hu, Hong-Ye, You, Yi-Zhuang, Khemani, Vedika, Verresen, Ruben, Vasseur, Romain. 2021-03-30. Topological and symmetry-enriched random quantum critical points. https://doi.org/10.1103/physrevb.103.l100207

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