title: Direct observation of antiferroquadrupolar ordering: resonant X-Ray scattering study of DyB2C2
abstract: Antiferroquadrupolar (AFQ) ordering has been conjectured in several rare-earth compounds to explain their anomalous magnetic properties. No direct evidence for AFQ ordering, however, has been reported. Using the resonant x-ray scattering technique near the Dy L(III) absorption edge, we have succeeded in observing the AFQ order parameter in DyB2C2 and analyzing the energy and polarization dependence. The much weaker coupling between the orbital degrees of freedom and the lattice in 4f electron systems than in 3d compounds makes them an ideal platform to study orbital interactions originating from electronic mechanisms.
authors.affiliation: Department of Physics, Tohoku University, Sendai, 980-8578 Japan and CREST, Japan Science and Technology Corporation, Tsukuba 305-0047, Japan.
authors.initials: K
authors.lastname: Hirota
authors.initials: N
authors.lastname: Oumi
authors.initials: T
authors.lastname: Matsumura
authors.initials: H
authors.lastname: Nakao
authors.initials: Y
authors.lastname: Wakabayashi
authors.initials: Y
authors.lastname: Murakami
authors.initials: Y
authors.lastname: Endoh