NMR/NQR study of the quadrupole orders in binary uranium-palladium intermetallic compound

Fujimoto, Tatsuya; Haga, Yoshinori   ; Sakai, Hironori   ; Tokunaga, Yo  ; Kambe, Shinsaku  ; Onuki, Yoshichika*

UPd shows the successive quadrupole orders at K, K and K. The phase transition at comes from the (1/2,0,1/2)-type quadrupole orders on quasi-cubic uranium-sublattice. On the other hand, the quadrupole states below are still controversial; while the Polarized Neutron Diffraction suggested the triple- structure, the Resonant X-ray Scattering assumed the canted quadrupole order. In addition, below , an antiferromagnetic order has been suggested, but the magnetic structure and so on are not still identified. To investigate the local symmetry of the quadruple order in UPd, we tried the nuclear quadrupole resonance, and we succeeded to find the first spin-echo signals from the UPd probed by Pd nuclei. In this paper, we report the nuclear properties of Pd isotope and discuss the characteristics of the quadrupole orders emerging in each temperature phases.