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arXiv · 1103.4429

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

Tiamhock Tay·Olexei I. Motrunich
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Abstract

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

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Tiamhock Tay, Olexei I. Motrunich. 2011-03-23. Variational study of J1-J2 Heisenberg model on Kagome lattice using projected Schwinger boson wave functions. https://doi.org/10.1103/physrevb.84.020404

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