Emergent self-duality in a long-range critical spin chain: From deconfined criticality to first-order transition
Sheng Yang, Zhiming Pan, Da-Chuan Lu, Xue-Jia Yu
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. A one-dimensional spin chain is an ideal platform for the theoretical investigation of these exotic phenomena, due to powerful simulation methods such as the density matrix renormalization group. Deconfined quantum criticality with self-duality at the critical point has been found in an extended short-range spin chain. In this work, we employ large-scale density matrix renormalization group simulations to investigate a critical spin chain with long-range power-law interaction $V(r)\ensuremath{\sim}1/{r}^{\ensuremath{\alpha}}$. Remarkably, we reveal that the long-range interaction drives the original deconfined criticality towards a first-order phase transition as $\ensuremath{\alpha}$ decreases. More strikingly, the emergent self-duality leads to an enlarged symmetry and manifests at these first-order critical points. This discovery is reminiscent of self-duality protected multicritical points, and it provides an example of the critical line with generalized symmetry. Our work has far-reaching implications for ongoing experimental efforts in Rydberg atom quantum simulators.