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Current reversal in polar flock at order-disorder interface.
Jay Prakash Singh1,2, Partha Sarathi Mondal1, Vivek Semwal1
1Indian Institute of Technology (BHU), Varanasi 221005, India.
Physical Review. E
|October 18, 2023
Summary
We explored self-propelled particles in a channel with varying noise levels, mimicking Josephson junctions. Increasing interface width caused order-to-disorder transitions and surprising current reversal, useful for active agent devices.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Self-propelled particles (SPPs) exhibit rich collective behaviors.
- Understanding particle dynamics in spatially varying environments is crucial.
- Josephson junctions in solid-state physics provide a model for controlled transitions.
Purpose of the Study:
- To investigate the collective behavior of polar SPPs in an order-disorder-order channel.
- To explore the influence of interface width on particle dynamics.
- To identify potential applications in active matter-based devices.
Main Methods:
- Simulated polar self-propelled particles in a three-region channel.
- Varied noise levels across regions to create order-disorder-order structure.
- Analyzed particle current and ordering as a function of interface width.
Main Results:
- Observed an order-to-disorder transition with increasing interface width.
- Identified current reversal within the interface for intermediate widths.
- Demonstrated a transition from coherent flow to interrupted current.
Conclusions:
- The system exhibits complex collective phenomena analogous to Josephson junctions.
- Interface properties significantly influence SPP dynamics, including current reversal.
- Findings suggest potential for designing active switching devices using SPPs.
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