| Title: |
The onset, evolution and magnetic braking of vortex lattice instabilities in nanostructured superconducting films |
| Authors: |
Adami, O. -A., Jelić, Ž. L., Xue, C., Abdel-Hafiez, M., Hackens, B., Moshchalkov, V. V., Milošević, M. V., Van de Vondel, J., Silhanek, A. V. |
| Publication Year: |
2015 |
| Collection: |
Condensed Matter |
| Subject Terms: |
Condensed Matter - Superconductivity |
| More Details: |
In 1976 Larkin and Ovchinnikov [Sov. Phys. JETP 41, 960 (1976)] predicted that vortex matter in superconductors driven by an electrical current can undergo an abrupt dynamic transition from a flux-flow regime to a more dissipative state at sufficiently high vortex velocities. Typically this transition manifests itself as a large voltage jump at a particular current density, so-called instability current density $J^*$, which is smaller than the depairing current. By tuning the effective pinning strength in Al films, using an artificial periodic pinning array of triangular holes, we show that a unique and well defined instability current density exists if the pinning is strong, whereas a series of multiple voltage transitions appear in the relatively weaker pinning regime. This behavior is consistent with time-dependent Ginzburg-Landau simulations, where the multiple-step transition can be unambiguously attributed to the progressive development of vortex chains and subsequently phase-slip lines. In addition, we explore experimentally the magnetic braking effects, caused by a thick Cu layer deposited on top of the superconductor, on the instabilities and the vortex ratchet effect |
| Document Type: |
Working Paper |
| DOI: |
10.1103/PhysRevB.92.134506 |
| Access URL: |
http://arxiv.org/abs/1512.01425 |
| Accession Number: |
edsarx.1512.01425 |
| Database: |
arXiv |
