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Optimizing the RVB state on a triangular lattice: Presence of the long-range order

Yong-Cong Chen
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Abstract

We present a Schwinger-boson approach for the RVB state of the spin-1/2 Heisenberg antiferromagnet on a triangular lattice. It is shown that Gutzwiller projection of the mean-field state that includes both antiferromagnetic and ferromagnetic decouplings leads to optimizing the RVB pair amplitudes within a self-consistent approximation. The resulting state yields, by Monte Carlo simulations, energies and spin-spin correlations in excellent agreement with the exact diagonalization result on finite lattices (up to 36 sites). We conclude that the optimized RVB wavefunction possesses a long-range three-sublattice order.

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Yong-Cong Chen. 1993-12-15. Optimizing the RVB state on a triangular lattice: Presence of the long-range order. https://doi.org/10.1142/s0217984994001242

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