S R Saha et al 2010 J. Phys.: Condens. Matter 22 072204 doi:10.1088/0953-8984/22/7/072204
S R Saha1, T Drye1, K Kirshenbaum1, N P Butch1, P Y Zavalij2 and Johnpierre Paglione1
Show affiliationsWe report superconductivity in single crystals of the new iron-pnictide system BaFe1.90Pt0.10As2 grown by a self-flux solution method and characterized via x-ray, transport, magnetic and thermodynamic measurements. The magnetic ordering associated with a structural transition at 139 K present in BaFe2As2 is completely suppressed by substitution of 5% Fe with Pt and superconductivity is induced at a critical temperature Tc = 23 K. Full diamagnetic screening in the magnetic susceptibility and a jump in the specific heat at Tc confirm the bulk nature of the superconducting phase. All properties of the superconducting state—including the transition temperature Tc, the lower critical field Hc1 = 200 mT, the upper critical field Hc2≈ 65 T, and the slope ∂Hc2/∂T—are comparable in value to those found in other transition metal-substituted BaFe2As2 series, indicating the robust nature of superconductivity induced by substitution of Group VIII elements.
74.25.Op Mixed states, critical fields, and surface sheaths
74.62.Dh Effects of crystal defects, doping and substitution
74.25.Fy Transport properties (electric and thermal conductivity, thermoelectric effects, etc.)
Issue 7 (24 February 2010)
Received 14 December 2009, in final form 15 January 2010
Published 2 February 2010
S R Saha et al 2010 J. Phys.: Condens. Matter 22 072204