Co and Mn doping effect in polycrystalline (Ca, La) and (Ca, Pr)FeAs2 superconductors. (17th April 2015)

• Record Type: Journal Article
• Authors: Yakita, Hiroyuki; Ogino, Hiraku; Sala, Alberto; Okada, Tomoyuki; Yamamoto, Akiyasu; Kishio, Kohji; Iyo, Akira; Eisaki, Hiroshi; Shimoyama, Jun-ichi
• Is Part Of: Superconductor science & technology. Volume 28:Number 6(2015:Jun.)
• Publication Date: 2015-04-17
• Subjects: iron based superconductor -- transition metals -- electron doping -- double doping; 74.25.-q; Superconductivity -- Periodicals; Superconductors -- Periodicals; 537.623
• DOI: 10.1088/0953-2048/28/6/065001
• Languages: English
• ISSNs: 0953-2048

Abstract

Abstract: The superconducting properties of Mn and Co doped (Ca, RE)FeAs2 ((Ca, RE)112: RE = La, Pr) were investigated. Co doping increased T c of (Ca, Pr)112 while Mn doping suppressed the superconductivity of (Ca, RE)112. The Co doped (Ca, La)112 exhibited a large diamagnetic screening, as well as sharper superconducting transition than Co-free (Ca, La)112. T c zero observed in the resistivity measurements increased from 14 to 30 K by Co doping, while was not increased. The critical current density, J c, of Co doped (Ca, La)112 was approximately 2.1 × 10 4 A cm −2 and 3.2 × 10 3 A cm −2 at 2 K and 25 K, respectively, at near zero field. These relatively high J c values and large diamagnetic screening observed in the susceptibility measurements of the polycrystalline bulks are evidence that Co doped (Ca, RE)112 compounds possess bulk superconductivity.