Irradiation-induced pinning in single-crystal and thin-film Tl2Ca2Ba2Cu3O10 superconductors.

摘要

Magnetization relaxation measurements were used to directly measure the effects of ion irradiation on magnetic flux pinning. The pinning potential (U) in a Tl(sub 2)Ca(sub 2)Ba(sub 2)Cu(sub 3)O(sub y) single crystal irradiated with 4.5 MeV protons, to a damage level of 4 (times) 10 (sup (minus)4) dpa, increased by (approx)25% at 25 K. In contrast, U for a highly oriented polycrystalline thin film irradiated with 300 keV He ions to a damage level of 2 (times) 10(sup (minus)4) dpa increased by only 5% at 25 K (and less at higher temperatures). Enhancement of the magnetization critical current density (J(sub cm)) is determined as a function of temperature and damage in the single crystal and thin film. High energy proton irradiation increased J(sub cm) in the single crystal by an order of magnitude at 25 K but had only a small effect on J(sub cm) in the thin film. 13 refs., 4 figs.