Vortex radiation in long narrow Josephson junctions: Theory and experiment
- Physikalisches Institut III, Universitaet Erlangen-Nuernberg, D-91058 Erlangen (Germany)
- Theoretische Physik III, Ruhr-Universitaet Bochum, D-44801 Bochum (Germany)
We study theoretically and experimentally the dynamics of vortices in long, extremely narrow Josephson junctions. Using a variational approach, the current-voltage characteristics are calculated for junctions of different widths. The analytically and numerically calculated current-voltage characteristics show good agreement. We find that the decrease of the junction width leads to a substantial increase of the maximum velocity of vortices. Due to the interaction with stray magnetic fields outside the junction, the vortices radiate Cherenkov waves as they move in the junction. Locking of the vortex oscillation frequency to that of the Cherenkov radiation leads to novel resonances on the current-voltage characteristics. We observe such resonances in experiments, and their voltage positions and current magnitudes are in qualitative agreement with our theoretical analysis.
- OSTI ID:
- 20719622
- Journal Information:
- Physical Review. B, Condensed Matter and Materials Physics, Journal Name: Physical Review. B, Condensed Matter and Materials Physics Journal Issue: 14 Vol. 72; ISSN 1098-0121
- Country of Publication:
- United States
- Language:
- English
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