Resonant X-ray scattering study of hidden order in URu2Si2 using a low-stress single crystal

We have studied a puzzling phase below 17.5 K of URu2Si2 by means of resonant X-ray scattering (RXS) near the U MIV absorption edge (E ~ 3.73 keV), using a high-quality single-crystalline sample with low residual stress. We reconfirm that a commensurate (003) superlattice reflection comes purely from antiferromegnetic dipolar order with ordering wave vector QAF = (1, 0, 0). No other traces of significant RXS have been detected in a major region of (h0l) plane, indicating absence of quadrupolar order within a searched Q range including a conceivable nesting vector Q* = (1.4, 0, 0).