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Bond order from disorder in the planar pyrochlore magnet

O. Tchernyshyov·O. A. Starykh·R. Moessner·A. G. Abanov
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Abstract

We study magnetic order in the Heisenberg antiferromagnet on the checkerboard lattice, a two-dimensional version of the pyrochlore network with strong geometric frustration. By employing the semiclassical (1/S) expansion we find that quantum fluctuations of spins induce a long-range order that breaks the four-fold rotational symmetry of the lattice. The ordered phase is a valence-bond crystal. We discuss similarities and differences with the extreme quantum case S = 1/2 and find a useful phenomenology to describe the bond-ordered phases.

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O. Tchernyshyov, O. A. Starykh, R. Moessner, A. G. Abanov. 2003-08-19. Bond order from disorder in the planar pyrochlore magnet. https://doi.org/10.1103/physrevb.68.144422

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