2009/12/31 by V. P. S. Awana, Anand Pal, Arpita Vajpayee +8
Materials Science · Physics and Astronomy · #Critical field #Doping #Electrical resistivity and conductivity #Electron #Iron-based superconductors research #Isostructural #Magnetic and transport properties of perovskites and related materials #Magnetization #Superconductivity #Superconductivity in MgB2 and Alloys #Transition temperature #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1063/1.3366601
published as J. Appl. Phys. 107, 09E146 (2010) · 14 Pages Text + Figs comments ([email protected])
openalex publication_date 2010/05/01 · arxiv created 2012/01/20 · arxiv updated 2015/05/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report synthesis, structural details, and magnetization of SmFe1−xCoxAsO with x ranging from 0.0 to 0.30. It is found that Co substitutes fully at Fe site in SmFeAsO in an isostructural lattice with slightly compressed cell. The parent compound exhibited known as the spin density wave (SDW) character is below at around 140 K. Successive doping of Co at Fe site suppressed the SDW transition for x=0.05 and later induced superconductivity for x=0.10, 0.15, and 0.20, respectively, at 14, 15.5, and 9 K. The lower critical field as seen from magnetization measurements is below 200 Oe. The appearance of bulk superconductivity is established by wide open isothermal magnetization M(H) loops. Superconductivity is not observed for higher content of Co, i.e., x≥0.30. Clearly the Co substitution at Fe site in SmFe1−xCoxAsO diminishes the Fe SDW character, introduces bulk superconductivity for x between 0.10 and 0.20 and finally becomes nonsuperconducting for x above 0.20. The Fe2+ site Co3+ substitution injects mobile electrons to the system and superconductivity appears; however direct substitution introduces simultaneous disorder in superconducting FeAs layer and thus superconductivity disappears for higher content of Co.