We investigate the deconfined quantum critical point (DQCP) candidate in the extended hard-core Bose-Hubbard model on the kagome lattice, employing quantum Monte Carlo simulations to study the entanglement entropy and the U(1) disorder operator. In stark contrast to findings in J-Q models and other candidates, the universal logarithmic correction coefficients for both quantities are found to be {positive}, consistent with a unitary conformal field theory (CFT). Crucially, the current central charge CJ, extracted from the small-angle behavior of the disorder operator, is enhanced by a factor of approximately {4/3} compared to that of the conventional 3D O(2) Wilson-Fisher fixed point. This enhancement {implies} a consistent explanation in the recently observed low-energy excitation spectrum at this DQCP, which features {two distinct linearly dispersing modes} with a velocity ratio of approximately three. Our results provide evidence that this quantum phase transition constitutes a genuine DQCP, characterized by coexisting fractionalized excitations that collectively modify its critical properties.
Cite
@article{arxiv.2601.13774,
title = {Entanglement entropy and disorder operator at kagome deconfined quantum criticality},
author = {Yan-Cheng Wang and Yan Zheng and Xue-Feng Zhang},
journal= {arXiv preprint arXiv:2601.13774},
year = {2026}
}