Resonant X-ray Scattering from URu2Si2
Tatsuya Nagao, Jun-ichi Igarashi
Journal of the Physical Society of Japan
Based on a localized crystal electric field model for the U^4+ in the (5f)^2-configuration, we analyze the resonant x-ray scattering spectra around U M_IV and M_V edges in URu_2Si_2, taking full Coulomb and spin-orbit interactions into account. We consider two level schemes, a singlet model of Santini and Amoretti and a doublet model of Ohkawa and Shimizu, and assume the antiferroquadrupolar order and the antiferromagnetic order as candidates for the ambient pressure phase and the high pressure
... phase. It is found that the spectral shapes as a function of photon energy are independent of the assumed level scheme, but are quite different between the antiferroquadrupole and antiferromagnetic phases, This may be useful to determine the character of the ordered phase.