Nature of the double superconducting transition in ?

✍ Scribed by M.-A. Méasson; D. Braithwaite; B. Salce; J. Flouquet; G. Lapertot; J. Pécaut; G. Seyfarth; J.-P. Brison; H. Sugawara; H. Sato

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 225 KB
• Volume: 378-380
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2006.01.169

✦ Synopsis

We present evidence which casts doubt on the intrinsic nature of the double superconducting transition (T c1 ¼ 1:89 K and T c2 ¼ 1:72 K) of the filled skutterudite compound PrOs 4 Sb 12 . Because of similar behaviors of T c1 and T c2 , the magnetic field and pressure dependence of the transitions are not conclusive. Further characterizations show a wide range of values of the ratio of the two specific heat jumps DCðT c1 Þ=DCðT c2 Þ on crystals from different batches and even within the same batch. Moreover, one sample exhibits a single sharp transition of 18 mK in width at T c ¼ 1:73 K. It has been characterized by specific heat, AC susceptibility and resistivity. A normalized specific heat jump DCðT c Þ=CðT c Þ of 25% which matches the sum of the two specific heat jumps in the other samples has been obtained.