Resonant X-Ray Scattering from the Quadrupolar Ordering Phase of CeB₆

Abstract

We theoretically investigate the origin of the resonant X-ray scattering (RXS) signal near the Ce L_III absorption edge in the quadrupolar ordering phase of CeB₆, considering the intersite interaction between the Γ₈ states in the initial state. The anisotropic charge distribution of the 4f states modulates the 5d states through the intra-atomic Coulomb interaction and thereby generates a large RXS superlattice intensity. The temperature and magnetic field dependence indicates that the induced dipolar and octupolar orders have little influence on the RXS spectra, in good agreement with the recent experimental results.