Gao, ChunpingLiu, JinghuChang, MaolinPu, HanChen, Li2022-12-132022-12-132022Gao, Chunping, Liu, Jinghu, Chang, Maolin, et al.. "Synthetic U(1) gauge invariance in a spin-1 Bose gas." <i>Physical Review Research,</i> 4, no. 4 (2022) American Physical Society: https://doi.org/10.1103/PhysRevResearch.4.L042018.https://hdl.handle.net/1911/114090Recent experimental realizations of the U(1) gauge invariance [Nature (London) 587, 392 (2020); Science 367, 1128 (2020)] open a door for quantum simulation of elementary particles and their interactions using ultracold atoms. Stimulated by such exciting progress, we propose a platform—a spin-1 Bose-Einstein condensate—to simulate the deconfined lattice Schwinger model. Unlike previous platforms, it is shown that the atomic interactions in the spin-1 condensate naturally lead to a matter-field interaction term which respects the U(1) gauge symmetry. As a result, a new Z3-ordered phase with threefold ground-state degeneracy emerges in the phase diagram. The Z3 phase connects to the disordered phase by a three-state Potts criticality, which is in contrast to the conventional Coleman's transition with Ising criticality. Furthermore, the ordered state is constructed by a set of weak quantum scars, which is responsible for the anomalously slow dynamics as it is quenched to a special point in the phase diagram. Our proposal provides a platform for extracting emergent physics in synthetic gauge systems with matter-field interactions.engPublished by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Journal articlePhysRevResearch-4-L042018https://doi.org/10.1103/PhysRevResearch.4.L042018