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arXiv · 2309.01652

Emergent self-duality in long range critical spin chain: from deconfined criticality to first order transition

Abstract

Over the past few decades, tremendous efforts have been devoted to understanding self-duality at the quantum critical point, which enlarges the global symmetry and constrains the dynamics. In this letter, we employ large-scale density matrix renormalization group simulations to investigate the critical spin chain with long-range interaction $V(r) \sim 1/r^α$. Remarkably, we reveal that the long-range interaction drives the deconfined criticality towards a first-order phase transition as $α$ decreases. More strikingly, the emergent self-duality leads to an emergent symmetry and manifests at these first-order critical points. This discovery is reminiscent of self-duality protected multicritical points and provides the example of the critical line with generalized symmetry. Our work has far-reaching implications for ongoing experimental efforts in Rydberg atom quantum simulators.

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Sheng Yang, Zhiming Pan, Da-Chuan Lu, Xue-Jia Yu. 2023-12-07. Emergent self-duality in long range critical spin chain: from deconfined criticality to first order transition. https://doi.org/10.1103/physrevb.108.245152

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