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

TL;DR

This paper investigates how long-range interactions in a quantum spin chain can induce gapless topological phases, revealing new algebraic and Gaussian universality classes with potential applications in quantum simulation.

Contribution

It demonstrates that long-range antiferromagnetic interactions can induce gapless topological phases and universality classes in quantum spin chains, expanding understanding of topological matter.

Findings

Long-range interactions induce algebraic topological phases.

Identification of topological Gaussian universality.

Potential for realizing gapless topological phases in quantum simulators.

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.