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Valence-bond crystal in a {111} slice of the pyrochlore antiferromagnet

Oleg Tchernyshyov·Hong Yao·R. Moessner
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Abstract

We investigate theoretically the ordering effect of quantum spin fluctuations in a Heisenberg antiferromagnet on a two-dimensional network of corner sharing tetrahedra. This network is obtained as a {111} slice of the highly frustrated pyrochlore lattice, from which it inherits the equivalence of all three pairs of opposite bonds of each tetrahedron. The lowest-order (in 1/S) quantum corrections partially lift the huge degeneracy of the classical ground state and select an ensemble of states with long-range valence-bond order.

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Oleg Tchernyshyov, Hong Yao, R. Moessner. 2004-02-07. Valence-bond crystal in a {111} slice of the pyrochlore antiferromagnet. https://doi.org/10.1103/physrevb.69.212402

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