Tuesday, May 7, 2013

1305.0844 (Simon Gerber et al.)

Microscopic Studies of the Normal and Superconducting State of

Simon Gerber, Jorge L. Gavilano, Marisa Medarde, Vladimir Pomjakushin, Christopher Baines, Ekaterina Pomjakushina, Kazimierz Conder, Michel Kenzelmann
We report on muon spin rotation (muSR) studies of the superconducting and magnetic properties of the ternary intermetallic stannide Ca3Ir4Sn13. This material has recently been at the focus of intense research activity due to a proposed interplay of ferromagnetic spin-fluctuations and superconductivity. In the temperature range T=1.6-200 K, we find that the zero field muon relaxation rate is very small and does not provide evidence for spin-fluctuations. The field-induced magnetization cannot be attributed to localized magnetic moments. In particular, our muSR data reveal that the anomaly observed in thermal and transport properties at T*~38 K is not of magnetic origin. Results for the transverse field muon relaxation rate at T=0.02-12 K, suggest that superconductivity emerges out of a normal state that is not of a Fermi liquid type. This is unusual for an electronic system lacking partially filled f-electron shells. The superconducting state is dominated by a nodeless order parameter with a London penetration length of lambda=416(1) nm and the electron-phonon pairing interaction is in the strong-coupling limit.
View original: http://arxiv.org/abs/1305.0844

No comments:

Post a Comment