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Antiferromagnetic Quantum Spins on the Pyrochlore Lattice

Hirokazu Tsunetsugu
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Abstract

The ground state of the S=1/2 Heisenberg antiferromagnet on the pyrochlore lattice is theoretically investigated. Starting from the limit of isolated tetrahedra, I include interactions between the tetrahedra and obtain an effective model for the spin-singlet ground state multiplet by third-order perturbation. I determine its ground state using the mean-field approximation and found a dimerized state with a four-sublattice structure, which agrees with the proposal by Harris et al. I also discuss chirality correlations and spin correlations for this state.

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Hirokazu Tsunetsugu. 2001-03-10. Antiferromagnetic Quantum Spins on the Pyrochlore Lattice. https://doi.org/10.1143/jpsj.70.640

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