https://doi.org/10.1140/epjb/e2002-00321-8
CEF nature of the magnetic excitations in ordered HoNi2B2C
1
Laboratory for Neutron Scattering,
ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
2
Ames Laboratory, Department of Physics and Astronomy,
Iowa State University, Ames, Iowa 50011, USA
3
Laboratoire Léon Brillouin, CEA/CNRS-Saclay, 91191 Gif-sur-Yvette, France
Corresponding author: a nordal.cavadini@psi.ch
Received:
25
February
2002
Revised:
13
May
2002
Published online:
14
October
2002
The magnetic excitations in the antiferromagnetic phase of HoNi2B2C are studied by inelastic neutron scattering on single crystals for the first time. Spectra measured at constant T=2 K along symmetry directions of the reciprocal space are well explained in terms of crystal electric field (CEF) magnetic excitons within the J=8 ground state multiplet of Ho3+. Very modest bandwidth with planar energy dispersion describes the magnetic exciton dynamics. A perturbative model approach consisting of the CEF states in the effective exchange mean-field provides a simple but applicable characterization of the experimental observations. The microscopic determination of the relevant exchange parameters is discussed in connection with previous works on the subject.
PACS: 74.70.Dd – Ternary, quaternary and multinary compounds / 75.10.Dg – Crystal-field theory and spin Hamiltonians / 78.70.Nx – Neutron inelastic scattering
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2002