Anisotropy and field dependence of critical current density in YBa2Cu3O7−δ epitaxial thin film

Abstract

The critical current density Jc of the epitaxial YBa2Cu3O7−δ thin film was measured as a function of applied magnetic field H up to 6 T for three special configurations: (1) H∥c axis and H⊥J; (2) H⊥c axis and H⊥J; (3) H⊥c axis and H∥J. We observed a large anisotropy of Jc(H) between H∥c axis and H⊥c axis with H⊥J, and a very small anisotropy of Jc(H) between H∥J and H⊥J with H⊥c axis. The field dependence of the critical current density can be well described by the modified Kim–Anderson model taking into account the Kramer scaling law. The weak dependence of the transport critical current density on its orientation relative to the applied magnetic field is discussed.

The collective flux pinning force in (Sm0.5Eu0.5)Ba2Cu3O7−δsuperconductors

“…The flux pinning mechanism is not definitely established. The scaling of the normalized pinning force density versus reduced applied magnetic field gave varied values of the parameters p and q, indicating the type of flux pinning mechanism, in the MTG RE123 samples [13][14][15][16][17][18]. In order to know what the effective pinning centre is in our samples, we also scale the flux pinning force at several temperatures in the following.…”

Normal-superconducting transition induced by high current densities inYBa2Cu3OGonzález1, Viña2, Currás3 et al. 2003Phys. Rev. B21060View full textAdd to dashboardCite

“…3 and 4, both J and E along the whole CVC's are approximately two orders of magnitude higher in films, and this includes J* and E*. The abundant results on transport properties for currents near the beginning of dissipation both for melt-textured samples 34 -37 and films [38][39][40][41] had already well established the existence of approximately a factor of 10 2 between J c values of both kind of samples. From the observation of the CVC's presented in this work, it can be stated that this feature is maintained along the whole CVC's.…”