THE ANISOTROPY OF TRANSPORT CRITICAL CURRENT DENSITIES IN TL2BA2CA2CU3OX THIN-FILMS UNDER MAGNETIC-FIELDS UP TO 20-T

The anisotropy of transport critical current densities (J(c)) in Tl2Ba2Ca2Cu3Ox thin film was measured resistively at 77 K under magnetic fields up to 20 T. When the magnetic field was applied parallel to the a-b plane (a-b plane//B), the of J(c) were 1.2 x 10(4) and 1.5 x 10(3) A/cm2 at 5 and 16 T, respectively. On the other hand, in fields perpendicular to the a-b plane (a-b plane perpendicular-to B), J(c) decreased drastically in the low field region. The irreversible magnetic field (B(c2)*) values for (a-b plane//B) and (a-b plane perpendicular-to B) were 22.0 and 0.89 T, respectively. The pinning force density (F(p) = J(c) x B) can be described by the Kramer scaling law, F(p)/F(p)max = 3.4 x b1/2(1 - b)2, where b (B/B(c2)*) is the reduced field. From measuring the angular dependence of J(c), as incident angle (theta) increased, J(c) decreased drastically.