Investigation of superconducting and normal-state properties of the filled-skutterudite system PrPt4Ge12-xSbx

Article

关键词: CORRELATED ELECTRON PHENOMENA;    TEMPERATURE;    TRANSITION;    LA;    DEPENDENCE;    BEHAVIOR;    FIELD;    HEAT;    FE;    RU;   

DOI  :  10.1103/PhysRevB.93.104507

来源: SCIE

【 摘 要 】

We report a study of the superconducting and normal-state properties of the filled-skutterudite system PrPt4Ge12-xSbx. Polycrystalline samples with Sb concentrations up to x = 5 were synthesized and investigated by means of x-ray diffraction, electrical resistivity, magnetic susceptibility, and specific heat measurements. We observed a suppression of superconductivity with increasing Sb substitution up to x = 4, above which no signature of superconductivity was observed down to 140 mK. The Sommerfeld coefficient, gamma, of superconducting specimens decreases with increasing x up to x = 3, suggesting that superconductivity may depend on the density of electronic states in this system. The specific heat for x = 0.5 exhibits an exponential temperature dependence in the superconducting state, reminiscent of a nodeless superconducting energy gap. We observed evidence for a weak rattling mode associated with the Pr ions, characterized by an Einstein temperature Theta(E) similar to 60 K for 0 <= x <= 5; however, the rattling mode may not play any role in suppressing superconductivity.

【 授权许可】

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