An Intercomparison of the Upper Critical Fields (H c 2 ) of Different Superconductors—YBa2Cu3 O 7, MgB2, NdFeAsO 0 . 8 F 0 . 2 , FeSe 0 . 5 Te 0 . 5 and Nb2PdS5

Abstract

Here, we report the comparison of the upper critical fields of different superconductors being calculated by two different theories, i.e. Werthamer Helfand Hohenburg (WHH) and Ginzberg Landau (GL). All the samples are synthesized through previously known solid-state reaction route. Phase purity is determined from the Rietveld refinement of powder X-ray diffraction (XRD) data. High-field (up to 14 T) magneto transport ρ(T)H of different superconductors is studied to estimate their upper critical field (H c2). The present intercomparison covers from cuprates (YBa2Cu3 O 7)–borides (MgB2)–Fe pnictides (NdFeAsO0.8 F 0.2) and chalcogenides (FeSe0.5Te0.5) to robust Nb2PdS5. The upper critical fields [ H c2(T)] at zero temperature are calculated by extrapolating the data using GL and WHH equations.