We have investigated magnetic flux relaxation at low temperatures in a 90 nm epitaxial coevaporated film on YBa2Cu3O7-δ superconductor. This film is characterized by a high critical current Jc of 3.5 × 1011 A m-2 at 4.2 K, and 1.3 × 1010 A m-2 at 77 K. Although Jc depends strongly on the applied magnetic field B the magnetic relaxation is only weakly dependent on B. Also the magnetic relaxation does not vanish at zero temperature, indicating that besides a thermally activated process there is another intrinsic process working.
|Number of pages||2|
|Publication status||Published - 1990|