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arXiv · 1109.3170

Long- to short-range magnetic order in fluorine-doped CeFeAsO

T. Shiroka·G. Lamura·S. Sanna·G. Prando·R. De Renzi·M. Tropeano·M. R. Cimberle·A. Martinelli·C. Bernini·A. Palenzona·R. Fittipaldi·A. Vecchione·P. Carretta·A. S. Siri·C. Ferdeghini·M. Putti
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Abstract

The evolution of the antiferromagnetic order parameter in CeFeAsO_{1-x}F_{x} as a function of the fluorine content x was investigated primarily via zero-field muon-spin spectroscopy. The long-range magnetic order observed in the undoped compound gradually turns into a short-range order at x=0.04, seemingly accompanied/induced by a drastic reduction of the magnetic moment of the iron ions. Superconductivity appears upon a further increase in doping (x>0.04) when, unlike in the cuprates, the Fe magnetic moments become even weaker. The resulting phase diagram evidences the presence of a crossover region, where the superconducting and the magnetic order parameters coexist on a nanoscopic range.

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T. Shiroka, G. Lamura, S. Sanna, G. Prando, R. De Renzi, M. Tropeano, M. R. Cimberle, A. Martinelli, C. Bernini, A. Palenzona, R. Fittipaldi, A. Vecchione, P. Carretta, A. S. Siri, C. Ferdeghini, M. Putti. 2011-09-14. Long- to short-range magnetic order in fluorine-doped CeFeAsO. https://doi.org/10.1103/physrevb.84.195123

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