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تسجيل مستخدم جديدAn inter comparison of the upper critical fields (Hc2) of different superconductors - YBa2Cu3O7, MgB2, NdFeAsO0.8F0.2, FeSe0.5Te0.5 and Nb2PdS5
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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 14Tesla) magneto transport r{ho}(T)H of different superconductors is studied to estimate their upper critical field (Hc2). The present inter comparison covers from Cuprates (YBa2Cu3O7) - Borides (MgB2) - Fe pnictides (NdFeAsO0.8F0.2) and chalcogenides (FeSe0.5Te0.5) to robust Nb2PdS5. The upper critical fields [Hc2(T)] at zero temperature are calculated by extrapolating the data using GL and WHH equations.
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Critical fields of four MgB2 thin films with a normal state resistivity ranging from 5 to 50 mWcm and Tc from 29.5 to 38.8 K were measured up to 28 T. Hc2(T) curves present a linear behavior towards low temperatures. Very high critical field values h
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