Rising Speed Limits for Fluxons via Edge-Quality Improvement in Wide MoSi Thin Films
- Author(s)
- Barbora Budinská, B. Aichner, D. Yu Vodolazov, M. Yu Mikhailov, F. Porrati, M. Huth, A. V. Chumak, W. Lang, O. V. Dobrovolskiy
- Abstract
Ultrafast vortex motion has recently become a subject of extensive investigations, triggered by the fundamental question regarding the ultimate speed limits for magnetic flux quanta and enhancements of single-photon detectors. In this regard, the current-biased quench of a dynamic flux-flow regime—flux-flow instability (FFI)—has turned into a widely used method for the extraction of information about the relaxation of quasiparticles (unpaired electrons) in a superconductor. However, the large relaxation times 𝜏𝜖 deduced from FFI for many superconductors are often inconsistent with the fast relaxation processes implied by their single-photon counting capability. Here, we investigate FFI in 15-nm-thick 182-𝜇m-wide MoSi strips with rough and smooth edges produced by laser etching and milling by a focused ion beam. For the strip with smooth edges we deduce, from current-voltage (𝐼-𝑉) curve measurements, a factor of 3 larger critical currents 𝐼𝑐, a factor of 20 higher maximal vortex velocities of 20 km/s, and a factor of 20 shorter 𝜏𝜖. We argue that for the deduction of the intrinsic 𝜏𝜖 of the material from the 𝐼-𝑉 curves, utmost care should be taken regarding the edge and sample quality and such a deduction is justified only if the field dependence of 𝐼𝑐 points to the dominating edge pinning of vortices.
- Organisation(s)
- Nanomagnetism and Magnonics, Electronic Properties of Materials
- External organisation(s)
- Russian Academy of Sciences, National Academy of Sciences of Ukraine (NASU), Johann Wolfgang Goethe-Universität Frankfurt am Main, Vienna Doctoral School in Physics
- Journal
- Physical Review Applied
- Volume
- 17
- No. of pages
- 12
- ISSN
- 2331-7019
- DOI
- https://doi.org/10.1103/PhysRevApplied.17.034072
- Publication date
- 03-2022
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103033 Superconductivity, 103018 Materials physics
- Keywords
- ASJC Scopus subject areas
- General Physics and Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/ce434ff3-eb9b-4666-8c70-61e46995bbe7