We show that Xe ion irradiation with 80 MeV to GdBa2Cu3Oy-coated conductors creates different morphologies of columnar defects (CDs) depending on the irradiation angles θi relative to the c-axis: continuous CDs with a larger diameter are formed for oblique irradiation at θi = 45°, whereas the same ion beam at a different angle (θi = 0°) induces the formation of discontinuous CDs. The direction-dependent morphologies of CDs significantly affect the angular behavior of the critical current density Jc. In particular, low-energy irradiation defects induce further improvement of Jc in a unique combination of irradiation angles of θi = 0° and ±45°: discontinuous CDs at θi = 0° and crossed CDs at θi = ±45° provide correlated pinning in a wide angular range, which is more strongly enhanced by each other via the pinning of kinks.

We systematically investigated the influence of columnar defects (CDs) on the flux dynamics around B || ab in YBa 2 Cu 3 O 7-δ (YBCO) films, where two types of the crossed CD configurations with the crossing angle relative to the c-axis, θ i =±30°and ±60°, were prepared by using 200 MeV Xe ion irradiation. The crossed CDs with θ i =±30°induce a peak of critical current density J c centered at B || c, which suggests a typical entanglement state of flux lines. The J c at B || ab, by contrast, is insensitive to the crossed CDs with θ i =±60°, which are crossing at ±30°around the ab-plane. In addition, the behaviors of the glass-liquid transition temperature T g and the dynamic critical exponent z indicate that the VG state develops at B || ab not only for θ i =±30°but also for θ i =±60°. The difference in the contribution of CDs to the flux dynamics for between θ i =±30°and ±60°also stands out at B || CDs, where the magnetic field for θ i =±60°is more tilted toward the ab-plane: the J c peak at B || CDs occurs in any magnetic field for θ i =±60°, whereas the correlated pinning state disappears in high magnetic fields for θ i =±30°. These results suggest that the pinning by CDs is angle-dependent due to the flux line structure with strong line tension around B || ab: CDs around the ab-plane can trap flux lines along their long axis only in much narrower angular-range, in comparison with CDs around the c-axis.