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Topological phases with long-range interactions.

ABSTRACT: Topological phases of matter are primarily studied in systems with short-range interactions. In nature, however, nonrelativistic quantum systems often exhibit long-range interactions. Under what conditions topological phases survive such interactions, and how they are modified when they do, is largely unknown. By studying the symmetry-protected topological phase of an antiferromagnetic spin-1 chain with 1/r ? interactions, we show that two very different outcomes are possible, depending on whether or not the interactions are frustrated. While unfrustrated long-range interactions can destroy the topological phase for ? ? 3, the topological phase survives frustrated interactions for all ? > 0. Our conclusions are based on strikingly consistent results from large-scale matrix-product-state simulations and effective-field-theory calculations, and we expect them to hold for more general interacting spin systems. The models we study can be naturally realized in trapped-ion quantum simulators, opening the prospect for experimental investigation of the issues confronted here.

SUBMITTER: Gong ZX

PROVIDER: S-EPMC6604642 | biostudies-literature | 2016

REPOSITORIES: biostudies-literature

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Topological phases with long-range interactions.

Gong Z-X ZX Maghrebi M F MF Hu A A Wall M L ML Foss-Feig M M Gorshkov A V AV

Physical review. B 20160101

Topological phases of matter are primarily studied in systems with short-range interactions. In nature, however, nonrelativistic quantum systems often exhibit long-range interactions. Under what conditions topological phases survive such interactions, and how they are modified when they do, is largely unknown. By studying the symmetry-protected topological phase of an antiferromagnetic spin-1 chain with 1/<i>r</i> <sup>α</sup> interactions, we show that two very different outcomes are possible, ...[more]

PMID: 31276075

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Dataset Information

Topological phases with long-range interactions.

Publications

Topological phases with long-range interactions.

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