Variational study of J1-J2 Heisenberg model on kagome lattice using projected Schwinger-boson wave functions

Motivated by the unabating interest in the spin-1/2 Heisenberg antiferromagnetic model on the kagome lattice, we investigate the energetics of projected Schwinger-boson (SB) wave functions in the J(1)-J(2) model with antiferromagnetic J(2) coupling. Our variational Monte Carlo results show that Sachdev's Q(1) = Q(2) SB ansatz has a lower energy than the Dirac spin liquid for J(2) greater than or similar to 0.08 J(1) and the q = 0 Jastrow-type magnetically ordered state. This work demonstrates that the projected SB wave functions can be tested on the same footing as their fermionic counterparts.