Published 2008
| Version v1
Publication
Synthesis, crystal structure, microstructure, transport and magnetic properties of SmFeAsO and SmFeAs(O0.93F0.07)
Description
SmFeAsO and the isostructural superconducting SmFeAs(O0.93F0.07) 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 Sm2O3, 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.
Additional details
Identifiers
- URL
- http://hdl.handle.net/11567/302771
- URN
- urn:oai:iris.unige.it:11567/302771
Origin repository
- Origin repository
- UNIGE