arXiv 1007.54602010-07-30cond-mat.supr-con

Nanoscopic coexistence of magnetic and superconducting states within the FeAs layers of CeFeAsO1-xFx

S. Sanna, R. De Renzi, T. Shiroka, G. Lamura, G. Prando, P. Carretta, M. Putti, A. Martinelli, M. R. Cimberle, M. Tropeano, A. Palenzona

备注：: 4 pages, 3 figs, accepted for publication as PRB Rapid comm
发表信息：: Phys. Rev. B 82, 060508(R) (2010)
DOI：: 10.1103/PhysRevB.82.060508

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We report on the coexistence of magnetic and superconducting states in CeFeAsO1-xFx for x=0.06(2), characterized by transition temperatures T_m=30 K and T_c=18 K, respectively. Zero and transverse field muon-spin relaxation measurements show that below 10 K the two phases coexist within a nanoscopic scale over a large volume fraction. This result clarifies the nature of the magnetic-to-superconducting transition in the CeFeAsO1-xFx phase diagram, by ruling out the presence of a quantum critical point which was suggested by earlier studies.

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