Muon knight shift measurements on PrPb in paraquadrupolar state

Ito, Takashi   ; Higemoto, Wataru  ; Oishi, Kazuki; Heffner, R. H.; Nishida, Nobuhiko*; Aoki, Yuji*; Onimaru, Takahiro*; Suzuki, Hiroyuki*

PrPb exhibits antiferroquadrupole ordering at T = 0.4 K. In the ordering phase, incommensurate structure of quadruple was found from recent experimental study and much attention is paid to this compound. We performed muon spin rotation and relaxation measurements on a single crystalline sample of PrPb. A quite anisotropic contact-coupling constant was extracted from the muon Knight shift, possibly concerned with nonspherical distribution of 4-electron at low temperature. The contact and dipole coupling constants are of comparable magnitudes, suggesting significance of strong hybridization between the electrons of Pr and the conduction electrons for incommensurate structure.