By implementing a unique magneto-optical system with ultrafast magnetic-field ramping-rate capability (up to 3 kT/s), we have been able to routinely generate and image dendritic flux instabilities in YBa2Cu3O7-x films. In the present work we study the effect of the film thickness on the dendritic instability. Dendritic avalanches in 50-600 nm thick films were magneto-optically imaged at 7 K, after ramping the magnetic field from zero to 60 mT at different rates. The data reveal a remarkable change in flux morphologies between the thin and the thicker films. While the former (50-250 nm) display well-developed dendritic patterns, the latter (350-600 nm) exhibit few avalanches with favored branch directions parallel to the film's edges. Several possible explanations for this behavior are discussed.
|Number of pages||7|
|Journal||Journal of Physics: Conference Series|
|State||Published - 19 Apr 2018|
|Event||28th International Conference on Low Temperature Physics, LT 2018 - Gothenburg, Sweden|
Duration: 9 Aug 2017 → 16 Aug 2017
Bibliographical noteFunding Information:
The authors thank Dr. Robert Semerad for preparation of the films and for helpful discussions. We also acknowledge a financial support from the Israel Science Foundation (ISF-164/12) and the Norwegian Research Council.
© Published under licence by IOP Publishing Ltd.