Strong pinning in high-temperature superconducting films

摘要: Detailed measurements of the critical current density ${j}_{c}$ ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ films grown by pulsed laser deposition reveal increase as a function film thickness. Both this thickness dependence and field are consistently described using generalization theory strong pinning Ovchinnikov Ivlev [Phys. Rev. B 43, 8024 (1991)]. From model, we deduce values defect ${(10}^{21} {\mathrm{m}}^{\ensuremath{-}3})$ elementary force, which in good agreement with generally accepted for ${\mathrm{Y}}_{2}{\mathrm{O}}_{3}$ inclusions. In absence clear evidence that is determined linear defects or modulations thickness, our model provides an alternative explanation rather universal found deposited different methods.