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Soft confinement of self-propelled rods: simulation and theory
Kevin J Modica1, Sho C Takatori1
1Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, CA 93106, USA. stakatori@ucsb.edu.
Soft Matter
|February 19, 2024
Summary
Active rods with nematic ordering show exponentially enhanced dispersion along their alignment direction, unlike passive rods. This study analyzes their dynamics under periodic potentials.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Passive rods and polymers exhibit nematic ordering under confinement.
- Transport in passive systems is limited by thermal diffusion.
- Understanding active matter dynamics is crucial for novel applications.
Purpose of the Study:
- To develop an analytical framework for active rod dynamics under periodic potentials.
- To investigate the structure and dispersion of self-propelled rods in 1D and 2D confinement.
- To quantify the enhancement in transport due to self-propulsion and nematic ordering.
Main Methods:
- Analytical framework development.
- Theoretical modeling.
- Numerical simulations.
Main Results:
- Self-propelled rods with nematic ordering generate significant convective fluxes.
- An exponential enhancement in active diffusivity along the director was demonstrated.
- Passive rods showed at most a 2-fold increase in diffusivity.
Conclusions:
- Nematic alignment and self-propulsion synergistically boost active diffusivity.
- The proposed framework accurately describes active rod behavior under periodic potentials.
- This work offers insights into transport phenomena in active soft matter systems.
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