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 $J_2\gtrsim 0.08J_1$ and the $\mathbf{q}=\mathbf{0}$ 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.