Abstract
Our recent success in triggering dendritic flux instabilities in YBa2Cu3O7-δ (YBCO) films by applying magnetic fields at ultrahigh rates is followed here by a detailed study of the effect as a function of the field ramp rate, Ba, and temperature, T. We trace the borderline in the Ba-T plane separating regions of smooth, gradual flux penetration and dendritic flux avalanches. In addition, we describe the changes in the dendritic morphology in the instability region as a result of changes in either Ba or T. Our experimental results, showing a monotonic increase of the avalanche threshold field ramp rate with temperature, are discussed in the framework of existing theories. On the basis of these theories we also explain the high stability of YBCO to dendritic avalanches as compared to, e.g., MgB2, identifying the flux flow resistivity, rather than any of the thermal parameters, as the main parameter governing the film stability.
| Original language | English |
|---|---|
| Article number | 054509 |
| Journal | Physical Review B |
| Volume | 94 |
| Issue number | 5 |
| DOIs | |
| State | Published - 10 Aug 2016 |
Bibliographical note
Publisher Copyright:© 2016 American Physical Society.
Funding
We also acknowledge financial support from the Israel Science Foundation (Grant No. ISF-164/12) and the Norwegian Research Council.
| Funders | Funder number |
|---|---|
| Israel Science Foundation | ISF-164/12 |
| Norges Forskningsråd |