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Published on: September 8, 2016
Disordering transitions and peak effect in polydisperse particle systems
C Reichhardt1, C J Olson Reichhardt
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Summary
In binary Yukawa particle systems, adding poorly pinned particles enhances pinning by increasing disorder. Optimal pinning occurs at specific defect densities, boosting the depinning threshold.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Physics
Background:
- Yukawa particle systems exhibit complex behaviors under disorder.
- Disordering transitions and peak effects in depinning phenomena are critical areas of study.
Purpose of the Study:
- To numerically investigate dispersity-driven disordering transitions in binary Yukawa particle systems.
- To understand the influence of quenched disorder and poorly pinned particles on depinning thresholds.
- To identify optimal conditions for pinning in binary mixtures.
Main Methods:
- Numerical simulations of binary Yukawa particle systems.
- Analysis of dispersity-driven disordering transitions.
- Investigation of quenched disorder and its impact on topological disorder.
- Characterization of the peak effect in depinning thresholds.
Main Results:
- A dispersity-driven disordering transition was observed in binary Yukawa systems.
- The addition of poorly pinned particles increases overall pinning by enhancing topological disorder.
- Optimal pinning in binary mixtures was found at topological defect fraction densities between 0.2 and 0.25.
- The peak effect in the depinning threshold is more pronounced in weakly pinning systems.
Conclusions:
- Binary Yukawa systems can be engineered for enhanced pinning through controlled addition of poorly pinned particles.
- Topological disorder plays a crucial role in mediating the peak effect.
- The findings provide insights into optimizing pinning properties in complex particle systems.
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