From cooperative paramagnetism to Neel order in Y2Ru2O7: neutron scattering measurements
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Date
2008-01-01
Journal Title
Journal ISSN
Volume Title
Publisher
American Physical Society
Abstract
Spin correlations in the pyrochlore antiferromagnet Y2Ru2O7 with Curie-Weiss temperature ΘCW* - 1100 K and critical temperature TN = 77 K were examined through neutron scattering. For TN < T < ΘCW / 3 the data show spin relaxation with a rate ℎΓ = 1.17(9)kBT. For T<TN spectral weight moves to higher energies with substantial changes up to 4kBTN. For T << TN there is a Δ = 11(1) meV energy gap and a pronounced spectral maximum at 19.7 meV. Throughout the temperature range examined, the wave vector dependence of inelastic scattering exhibits a broad peak for Qd ≈ 3.8 (d is the Ru-Ru spacing) consistent with dipolar spin correlations.
Description
Keywords
yttrium compounds, ruthenium compounds, neutron diffraction, paramagnetism, spin correlations, pyrochlore antiferromagnet, Curie-Weiss temperature, critical temperature, neutron scattering, spin relaxation, inelastic scattering, Neel temperature, magnetic susceptibility, energy gap, antiferromagnetic materials, temperature 77 K, temperature -1100 K, Y2Ru2O7
Citation
Physical Review B (Condensed Matter and Materials Physics) 1 Jan. 2008, vol.77, no.2, pp. 020405-1-4