The critical current density Jc as a function of the temperature T, magnetic field intensity H and angle between the direction of applied magnetic field and the c-axis of the samples was measured on epitaxial 10at.% Ca-substituted YBa2Cu3O7-δ (YCBCO) thin films grown by the pulsed laser deposition technique on (001)-SrTiO3 (STO) and CeO2 buffered r-cut Al2O3 (CAO) substrates. Films exhibited comparable values of critical temperature (T c∼78K) while higher self-field Jc values for SrTiO3 were observed. Dissipation regimes related to growth boundary and intra-grain pinning mechanisms showed a qualitatively similar contribution for YCBCO films deposited on both substrates when the applied magnetic field direction is parallel to the c-axis ( ≤ 0°). However, a weaker efficiency of pinning related to growth boundaries as well as a wider field range where this dissipation mechanism is active were observed for films grown on CeO 2-buffered sapphire. These films exhibited a broad peak centred at ≤ 0° in the Jc versus angle behaviour, not observed using a SrTiO3 substrate. The analysis of the Jc(H) dependences collected at ≤ 90° revealed that this feature can be partially ascribed to a dramatic decrease of the intrinsic pinning efficiency. © IOP Publishing Ltd.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)
- Condensed Matter Physics
- Electronic, Optical and Magnetic Materials
Augieri, A., Celentano, G., Gambardella, U., Halbritter, J., & Petrisor, T. (2007). Analysis of angular dependence of pinning mechanisms on Ca-substituted YBa2Cu3O7-δ epitaxial thin films. Superconductor Science and Technology, 20(4), 381 - 385. . https://doi.org/10.1088/0953-2048/20/4/013