# $Z 2$ spin liquid and chiral antiferromagnetic phase in Hubbard model on the honeycomb lattice: duality between Schwinger-fermion and Schwinger-boson representations - Condensed Matter > Strongly Correlated Electrons

$Z 2$ spin liquid and chiral antiferromagnetic phase in Hubbard model on the honeycomb lattice: duality between Schwinger-fermion and Schwinger-boson representations - Condensed Matter > Strongly Correlated Electrons - Download this document for free, or read online. Document in PDF available to download.

Abstract: In our previous work, we identify the Sublattice-Pairing State SPS inSchwinger-fermion representation as the spin liquid phase discovered in recentnumerical study on a honeycomb lattice. In this paper, we show that SPS isidentical to the zero-flux $Z 2$ spin liquid in Schwinger-boson representationfound by Wang\cite{Wang2010} by an explicit duality transformation. SPS isconnected to an \emph{unusual} antiferromagnetic ordered phase, which we termas chiral-antiferromagnetic CAF phase, by an O4 critical point. CAF phasebreaks the SU2 spin rotation symmetry completely and has three Goldstonemodes. Our results indicate that there is likely a hidden phase transitionbetween CAF phase and simple AF phase at large $U-t$. We propose numericalmeasurements to reveal the CAF phase and the hidden phase transition.

Author: Yuan-Ming Lu, Ying Ran

Source: https://arxiv.org/