2008/06/13 by A. Martinelli, M. Ferretti, P. Manfrinetti +8 · 1 citation
Business, Management and Accounting · Chemistry · Materials Science · Physics and Astronomy · #Chemistry #Condensed matter physics #Corporate Taxation and Avoidance #Crystal structure #Crystallography #Electrical resistivity and conductivity #Iron-based superconductors research #Isostructural #Magnetic field #Magnetism #Magnetization #Materials science #Metallurgy #Microstructure #Physics #Rare-earth and actinide compounds #Rietveld refinement #Superconductivity #cond-mat.supr-con
paper · pdf · doi:10.1088/0953-2048/21/9/095017
published as Superconductor Science and Technology 21 (2008) 095017 · Submitted to: Superconductor Science and Technology
arxiv created 2008/06/13 · openalex publication_date 2008/07/15 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
SmFeAsO and the isostructural superconducting SmFeAs(O 0.93 F 0.07 ) phase were prepared and characterized by means of Rietveld refinement of x-ray powder diffraction data, scanning electron microscope observation, transmission electron microscope analysis, and resistivity and magnetization measurements. Sintering treatment strongly improves the grain connectivity, but, on the other hand, induces a competition between the thermodynamic stability of the oxy-pnictide and Sm 2 O 3 , thus affecting the sample purity. In the pristine sample both magnetization and resistivity measurements clearly indicate that two different sources of magnetism are present: the former related to Fe ordering at T ∼140 K and the latter due to the Sm ions that order antiferromagnetically at low temperature. The feature at 140 K disappears in the F-substituted sample, and a superconducting transition appears, at low temperatures. The magnetoresistivity curves of the F-substituted sample probably indicate very high critical field values.