Rainbow scars: From area to volume law

Langlett, Christopher M.; Yang, Zhi-Cheng; Wildeboer, Julia; Gorshkov, Alexey V.; Iadecola, Thomas; Xu, Shenglong

doi:10.1103/physrevb.105.l060301

Title: Rainbow scars: From area to volume law

Journal Article · 06 February 2022 · Physical Review. B

DOI: https://doi.org/10.1103/physrevb.105.l060301 · OSTI ID:1979778

Langlett, Christopher M. ^[1];

^[2]; Wildeboer, Julia ^[3];

^[2];

^[3];

^[4]

Texas A & M Univ., College Station, TX (United States); OSTI
Univ. of Maryland, College Park, MD (United States); National Inst. of Standards and Technology (NIST), College Park, MD (United States)
Iowa State Univ., Ames, IA (United States)
Texas A & M Univ., College Station, TX (United States)

Quantum many-body scars (QMBS) constitute a new quantum dynamical regime in which rare “scarred” eigenstates mediate weak ergodicity breaking. One open question is to understand the most general setting in which these states arise. In this work, we develop a generic construction that embeds a new class of QMBS, rainbow scars, into the spectrum of an arbitrary Hamiltonian. Unlike other examples of QMBS, rainbow scars display extensive bipartite entanglement entropy while retaining a simple entanglement structure. Specifically, the entanglement scaling is volume-law for a random bipartition, while scaling for a fine-tuned bipartition is subextensive. When internal symmetries are present, the construction leads to multiple, and even towers, of rainbow scars revealed through distinctive non-thermal dynamics. Remarkably, certain symmetries can lead rainbow scars to arise in translation-invariant models. To this end, we provide an experimental road map for realizing rainbow scar states in a Rydberg-atom quantum simulator, leading to coherent oscillations distinct from the strictly sub-volume-law QMBS previously realized in the same system.

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Research Organization:: Duke Univ., Durham, NC (United States); Univ. of Maryland, College Park, MD (United States)

Sponsoring Organization:: National Science Foundation (NSF); USDOE; USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)

Grant/Contract Number:: SC0019040; SC0019449; SC0020312

OSTI ID:: 1979778

Journal Information:: Physical Review. B, Journal Name: Physical Review. B Journal Issue: 6 Vol. 105; ISSN 2469-9950

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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