The magnetic and transport properties of high-critical-current Tl2Ba2Ca2Cu3O<i>x</i> superconducting thin films

Abstract

Highly c-axis-oriented Tl2Ba2Ca2Cu3Ox superconducting thin films with the critical current density as high as 1×107 A/cm2 at 87 K were obtained by single-target dc sputtering on LaAlO3(100) substrates followed by encapsulated compensate annealing. The strong linear temperature dependence of zero-field critical current at low temperatures suggests a creep-dominated behavior. Preliminary field dependence studies on the critical current density in low-field regime (&amp;lt;2 kOe) shows no evidence of hysteresis commonly encountered in films with higher granularity. The scaling behavior of the global pinning force density exhibits strong resemblance to conventional type-II superconductors with the pinning force density of the same order of magnitude as that in strong pinned NbN thin films.