The flux pinning behaviors for the heavy ion irradiated Er123 films are investigated based on the detailed Jc(B,T,θ) properties. The double peaks of Fp curves for B // c appear in case of the matching field of 0.3 T along c-axis and 1.7 T tilted from c-axis. In addition, the peaks on Jc (θ) at θ = 0° (B // c) , which originate from the columnar defects, decrease with increasing magnetic field but increase again near the irreversibility field.We found that the cooperation model of the c-axis correlated and random pinning centers can describe the observed double peak behavior of Fp(B) and the angular dependence of Jc related to the correlated pinning.
- Columnar defect
- Critical current density
- Flux pinning
- High-temperature superconducting film