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Updated: Jul 25, 2026
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Dynamic phases and the peak effect in dirty type II superconductors
van Otterlo A1, Scalettar, Zimanyi
1Physics Department, University of California, Davis, California 95616, USA.
Physical Review Letters
|October 6, 2000
Summary
We investigated driven vortex matter dynamics. Critical current peaks were observed during transitions and melting, consistent with simulations and YBCO crystal experiments, revealing a "moving solid" phase at higher drives.
Area of Science:
- Condensed matter physics
- Superconductivity
- Vortex dynamics
Background:
- Driven vortex matter exhibits complex phase transitions.
- Understanding critical current behavior is crucial for superconducting applications.
Purpose of the Study:
- To numerically and experimentally investigate the dynamics of driven vortex matter.
- To characterize the critical current behavior across phase transitions.
- To explore the influence of disorder on vortex matter at higher drives.
Main Methods:
- London-Langevin simulations.
- Transport measurements on untwinned YBCO crystals.
Main Results:
- Critical current shows a peak across the Bragg glass to vortex glass transition and melting line.
- Observed peak is associated with a crossing of current-voltage (I-V) curves.
- Vortices reorder into a "moving solid" phase at higher drives, with disorder effects modeled by a "shaking temperature" inversely proportional to velocity.
Conclusions:
- The study provides a comprehensive understanding of driven vortex matter dynamics.
- Experimental results align with numerical simulations, validating the findings.
- Disorder plays a significant role in the emergent "moving solid" phase.
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