Resonant X-ray scattering in URu2Si2

Using two types of the localized crystal electric field models based on the singlet and the doublet schemes, we investigate the resonant X-ray scattering spectra of URu2Si2 near the U M-1v and M-v absorption edges assuming three kinds of the ordering phases, a dipolar and two components of the quadrupolar ordering phases. We show that both schemes give similar results. The spectra from each ordering phase around the U M-1v and M-v edges exhibit a variety of features depending on the photon energy, the photon polarization and the azimuthal angle, which can provide useful clues to characterize the nature of the so-called hidden ordering phase in URu2Si2. The spectra from the dipole phase may be interpreted as a signal from newly discovered antiferromagnetic phase under pressure. (c) 2005 Elsevier B.V. All rights reserved.