Muon spin rotation and relaxation in Pr${}_{1-x}$Nd${}_x$Os${}_4$Sb${}_{12}$: Paramagnetic states

Abstract

Positive-muon (${\mu }^{+}$) Knight shifts have been measured in the paramagnetic states of Pr${}_{1-x}$Nd${}_x$Os${}_4$Sb${}_{12}$ alloys, where $x=$ 0, 0.25, 0.45, 0.50, 0.55, 0.75, and 1.00. In Pr-substituted NdOs${}_4$Sb${}_{12}$ ($x\le$ 0.75), but not in NdOs${}_4$Sb${}_{12}$, Clogston-Jaccarino plots of ${\mu }^{+}$ Knight shift~$K$ versus magnetic susceptibility~$\chi$ exhibit an anomalous saturation of $K(\chi )$ at $\sim -$0.5% for large susceptibilities (low temperatures), indicating a reduction of the coupling strength between ${\mu }^{+}$ spins and $4f$ paramagnetism for temperatures $\lesssim$ 15~K. We speculate that itinerant Pr${}^{3+}$ quadrupolar excitations, invoked to mediate the superconducting Cooper-pair interaction, might modify the ${\mu }^{+}$-$4f$ ion indirect spin-spin interaction.

7 pages, 9 figures, accepted for publication in Physical Review B

References in corpus (4)

• Direct Observation of Quadrupolar Excitons in the Heavy-Fermion Superconductor PrOs${}_4$Sb${}_{12}$
• Eliashberg theory of superconductivity and inelastic rare-earth impurity scattering in filled skutterudite La${}_{1-x}$Pr${}_x$Os${}_4$Sb${}_{12}$
• Field dependent mass enhancement in Pr_{1-x}La_xOs_4Sb_12 from aspherical Coulomb scattering
• Muon spin rotation and relaxation in Pr${}_{1-x}$Nd${}_x$Os${}_4$Sb${}_{12}$: Magnetic and superconducting ground states

Cited by in corpus (1)

• Nodeless superconductivity and preserved time-reversal symmetry in the noncentrosymmetric Mo3P superconductor