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Magnetic Properties of (VO)_2P_2O_7 from Frustrated Interchain Coupling

G. S. Uhrig·B. Normand
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Abstract

Neutron-scattering experiments on (VO)_2P_2O_7 reveal both a gapped magnon dispersion and an unexpected, low-lying second mode. The proximity and intensity of these modes suggest a frustrated coupling between the alternating spin chains. We deduce the minimal model containing such a frustration, and show that it gives an excellent account of the magnon dispersion, static susceptibility and electron spin resonance absorption. We consider two-magnon states which bind due to frustration, and demonstrate that these may provide a consistent explanation for the second mode.

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G. S. Uhrig, B. Normand. 1998-12-11. Magnetic Properties of (VO)_2P_2O_7 from Frustrated Interchain Coupling. https://doi.org/10.1103/physrevb.58.r14705

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