Possible uniform-flux chiral spin liquid states in the SU(3) ring-exchange model on the triangular lattice (1302.4512v4)

Abstract: We consider a SU(3) model with antiferromagnetic three-site ring exchanges, in addition to two-site exchanges, on the triangular lattice. We first present numerical site-factorized state studies on the magnetic ordered states, which shows two different three-sublattice-ordered states, the antiferro-quadrupolar phase and the standard 120^o anti-ferromagnetic phase, along the axis of the strength of the three-site ring exchanges. We further study the model using slave-fermion mean field approaches in which we rewrite the exchange operators in terms of three flavors of fermions. At the mean-field level, we find the main competing trial states are the trimer state (triangular plaquette state), gapped uniform \pi/3-flux chiral spin liquid, and gapped uniform 2\pi/3-flux chiral spin liquid. The filled band of the \pi/3-flux chiral spin liquid has Chern number +1, and that of the 2\pi/3-flux chiral spin liquid has Chern number +2. We also give the effective Chern-Simons theory for each chiral spin liquid at the mean-field level.