Flux creep phenomenon in the diamagnetic magnetization of high-Jc YBa2Cu3O7 films prepared by CVD has been measured in magnetic fields up tp 50kOe. The activation energy U0 was estimated from the flux creep rate as a function of temperature at various magnetic fields. The U0 value increases almost linearly with increasing temperature and after taking a broad maximum at about 60K decreases both for H⊥c-axis and H//c-axis. The U0 value near the maximum is suppressed by increasing magnetic field, although it is almost independent of the magnetic field at low temperature. Moreover, we observed that the anisotropy in the U0 value was very small.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Energy Engineering and Power Technology
- Electrical and Electronic Engineering