Abstract
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We report on the effect of in situ hydrostatic pressure on the enhancement of the in-magneticfield
critical current density parallel to the crystallographic c-axis and vortex pinning in epitaxial
Y(Dy0.5)Ba2Cu3O7−δ coated conductors prepared by metal organic deposition. Our results show
that in situ hydrostatic pressure greatly enhances the critical current density at high fields and
high temperatures. At 80 K and 5 T we observe a ten-fold increase in the critical current density
under the pressure of 1.2 GPa, and the irreversibility line is shifted to higher fields without
changing the critical temperature. The normalized magnetic relaxation rate shows that vortex
creep rates are strongly suppressed due to applied pressure, and the pinning energy is
significantly increased based on the collective creep theory. After releasing the pressure, we
recover the original superconducting properties. Therefore, we speculate that the in situ
hydrostatic pressure exerted on the coated conductor enhances the pinning of existing extended
defects. This is totally different from what has been observed in REBa2Cu3O7−δ melt-textured
crystals, where the effect of pressure generates point-like defects.