Paramagnetic neutron scattering from the Heisenberg ferromagnet EuO

Journal Article · Sat Mar 01 04:00:00 EST 1986 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.33.3012· OSTI ID:5954592

Boeni, P; Shirane, G

Paramagnetic neutron scattering from the insulating Heisenberg ferromagnet EuO has been studied through the entire Brillouin zone. The measured linewidth GAMMA of the quasielastic scattering at T/sub c/ follows the predictions of dynamic scaling GAMMA = Aq/sup 2.5/ up to momentum transfers q = 0.4 A/sup -1/. The new results disagree with an early work by Passell et al., where a smaller exponent and smaller linewidths have been reported, but agree perfectly with recent spin-echo measurements performed by Mezei at very small q. The q/sup 2.5/ dependence of GAMMA is now established over nearly four decades in energy. At large momentum transfers the energy distribution evolves into a three-peaked structure with much more spectral weight near E = 0, in disagreement with the two-peaked structure reported by Mook. The cross sections near the zone boundary are in quantitative agreement with recent calculations by Young and Shastry. We conjecture that peaks at finite energy occur in EuO and EuS because of the short-ranged exchange interactions.

• Research Organization: Brookhaven National Laboratory, Upton, New York 11973
• OSTI ID: 5954592
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 33:5; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
BRILLOUIN ZONES
CHALCOGENIDES
COHERENT SCATTERING
CROSS SECTIONS
CRYSTAL MODELS
DATA
DIFFRACTION
ELASTIC SCATTERING
ENERGY SPECTRA
EUROPIUM COMPOUNDS
EUROPIUM OXIDES
EXPERIMENTAL DATA
FERROMAGNETIC MATERIALS
HEISENBERG MODEL
INFORMATION
LINE WIDTHS
MAGNETIC MATERIALS
MAGNETISM
MATERIALS
MATHEMATICAL MODELS
MOMENTUM TRANSFER
NEUTRON DIFFRACTION
NUMERICAL DATA
OXIDES
OXYGEN COMPOUNDS
PARAMAGNETISM
RARE EARTH COMPOUNDS
SCALING LAWS
SCATTERING
SPECTRA
SPIN ECHO
ZONES