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Coupled Magnetic Excitations in Single Crystal PrBa2Cu3O6.2

S. J. S. Lister·A. T. Boothroyd·N. H. Andersen·B. H. Larsen·A. A. Zhokhov·A. N. Christensen·A. R. Wildes
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Abstract

The dispersion of the low-energy magnetic excitations of the Pr sublattice in PrBa2Cu3O6.2 is determined by inelastic neutron scattering measurements on a single crystal. The dispersion, which shows the effect of interactions with the Cu spin-waves, is well described by a model of the coupled Cu-Pr magnetic system. This enables values for the principal exchange constants to be determined, which suggest that both Pr-Pr and Cu-Pr interactions are important in producing the anomalously high ordering temperature of the Pr sublattice. Measurements of the Cu optic spin wave mode show that the inter-layer Cu-Cu exchange is significantly lower than in YBa2Cu3O6.2.

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S. J. S. Lister, A. T. Boothroyd, N. H. Andersen, B. H. Larsen, A. A. Zhokhov, A. N. Christensen, A. R. Wildes. 2001-05-15. Coupled Magnetic Excitations in Single Crystal PrBa2Cu3O6.2. https://doi.org/10.1103/physrevlett.86.5994

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