Deconfined quantum criticality and emergent SO(5) symmetry in fermionic systems

Deconfined quantum criticality with emergent SO(5) symmetry in correlated systems remains elusive. Here, by performing numerically-exact state-of-the-art quantum Monte Carlo (QMC) simulations, we show convincing evidences of deconfined quantum critical points (DQCP) between antiferromagnetic and valence-bond-solid phases in the extended Hubbard model of fermions on the honeycomb lattice with large system sizes. We further demonstrate evidences of the SO(5) symmetry at the DQCP. Moreover, it is the first time that the critical exponents obtained at the DQCP are consistent with the rigourous conformal bounds. Consequently, we establish a promising arena of DQCP with emergent SO(5) symmetry in interacting systems of fermions. Its possible experimental relevances in correlated systems such as graphene-family materials will be discussed briefly [1].
[1] Zi-Xiang Li, Shao-Kai Jian, and Hong Yao, arXiv:1904.10975