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Abstract |
We report the influence of random point defects introduced by 3 MeV proton irradiation (doses of 0.5 × 10 16 , 1 × 10 16 , 2 × 10 16 and 6 × 10 16 cm −2 ) on the vortex dynamics of co-evaporated 1.3 μ m thick, GdBa 2 Cu 3 O 7− δ coated conductors. Our results indicate that the inclusion of additional random point defects reduces the low field and enhances the in-field critical current densities J c . The main in-field J c enhancement takes place below 40 K, which is in agreement with the expectations for pinning by random point defects. In addition, our data show a slight though clear increase in flux creep rates as a function of irradiation fluence. Maley analysis indicates that this increment can be associated with a reduction in the exponent μ characterizing the glassy behavior. |
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