2003/07/31 by V. Ferrando, P. Manfrinetti, D. Marré +5 · 1 citation
Materials Science · Mathematics · Physics and Astronomy · #Combinatorics #Condensed matter physics #Critical field #Electrical resistivity and conductivity #Field (mathematics) #Iron-based superconductors research #Magnetic field #Materials science #Mathematics #Omega #Optics #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Saturation (graph theory) #Scattering #Superconductivity #Superconductivity in MgB2 and Alloys #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.68.094517
published as Phys.Rev.B 68, 094517 (2003) · 17 pages, 3 figures
openalex publication_date 2003/09/24 · arxiv created 2003/09/26 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Upper critical fields of four MgB2 thin films were measured up to 28 T at Grenoble High Magnetic Field Laboratory. The films were grown by pulsed laser deposition and showed critical temperatures ranging between 29.5 and 38.8 K and resistivities at 40 K varying from 5 to 50 \ensuremathμ\ensuremathΩ cm. The critical fields in the perpendicular direction turned out to be in the 13--24 T range while they were estimated to be in 42--57 T range for ab planes. In contrast to the prediction of the BCS theory, we did not observe any saturation at low temperatures: a linear temperature dependence is exhibited even at lowest temperatures at which we made the measurements. Moreover, the critical field values seemed not to depend on the normal state resistivity value. In this paper, we analyze these data considering the multiband nature of superconductivity in MgB2. We will show how the scattering mechanisms that determine critical fields and resistivity can be different.