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arXiv · 2406.01974

Gifts from long-range interaction: Emergent gapless topological behaviors in quantum spin chain

Sheng Yang·Hai-Qing Lin·Xue-Jia Yu
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Abstract

Topology in condensed matter physics is typically associated with a bulk energy gap. However, recent research has shifted focus to topological phases without a bulk energy gap, exhibiting nontrivial gapless topological behaviors. In this letter, we explore a cluster Ising chain with long-range antiferromagnetic interactions that decay as a power law with the distance. Using complementary numerical and analytical techniques, we demonstrate that long-range interactions can unambiguously induce an algebraic topological phase and a topological Gaussian universality, both of which exhibit nontrivial gapless topological behaviors. Our study not only provides a platform to investigate the fundamental physics of quantum many-body systems but also offers a novel route toward searching for gapless topological phases in realistic quantum simulators.

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Sheng Yang, Hai-Qing Lin, Xue-Jia Yu. 2024-06-04. Gifts from long-range interaction: Emergent gapless topological behaviors in quantum spin chain. https://doi.org/10.1038/s42005-025-01947-z

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