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High-energy Cu spin excitations in PrBa2Cu3O6+x

A. T. Boothroyd·N. H. Andersen·B. H. Larsen·A. A. Zhokhov·C. D. Frost·D. T. Adroja
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Abstract

This paper describes high-energy neutron inelastic scattering measurements of propagating magnetic excitations in PrBa2Cu3O6+x (x approx 0.2 and 0.93). The measurements probe the acoustic and optic modes of the antiferromagnetically-ordered copper--oxygen bilayers in the energy range 50-150 meV. The observed magnon dispersion can be described satisfactorily in this energy range by a spin wave model including intra- and inter-layer nearest-neighbour exchange constants J_parallel and J_perp. We find J_parallel = 127 +/- 10 meV and J_perp = 5.5 +/- 0.9 meV. The value of J_parallel is virtually the same as that found in YBa2Cu3O6.2, but J_perp is a factor of two smaller. To within experimental error the values of J_parallel and J_perp for PrBa2Cu3O6+x do not vary with oxygen doping.

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A. T. Boothroyd, N. H. Andersen, B. H. Larsen, A. A. Zhokhov, C. D. Frost, D. T. Adroja. 2005-02-18. High-energy Cu spin excitations in PrBa2Cu3O6+x. https://doi.org/10.1103/physrevb.71.094514

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