Onset, evolution, and magnetic braking of vortex lattice instabilities in nanostructured superconducting films
(2015) Physical review. B, Condensed matter and materials physics — Vol. 92, n° 13, p. 134506-134501 (2015)
Files
Adami_PRB2015-1-16-10-2015.pdf
Restricted Access - Adobe PDF
- 1016.82 KB
Details
- Authors
- Abstract
- In 1976, Larkin and Ovchinnikov [Zh. Eksp. Teor. Fiz. 68, 1915 (1975) [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.
- Affiliations
Citations
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. (2015). Onset, evolution, and magnetic braking of vortex lattice instabilities in nanostructured superconducting films. Physical review. B, Condensed matter and materials physics, 92(13), 134506-134501. https://doi.org/10.1103/PhysRevB.92.134506 (Original work published 2015)