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Obstruction enhances the diffusivity of self-propelled rod-like particles
Hamidreza Khalilian1, Hossein Fazli1
1Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
The Journal of Chemical Physics
|November 3, 2016
Summary
Self-propelled particle diffusion in 3D is affected by obstacles. Particle diffusivity can unexpectedly increase with more obstacles due to self-propulsion and shape anisotropy.
Area of Science:
- Physics
- Soft Matter Physics
- Statistical Mechanics
Background:
- Understanding particle diffusion is crucial in various fields.
- Self-propelled particles exhibit complex behaviors influenced by their environment.
- Obstacles can significantly alter particle dynamics.
Purpose of the Study:
- To investigate the diffusion of 3D self-propelled particles with obstacles.
- To analyze the impact of obstacle density on particle diffusivity.
- To explore the relationship between self-propulsion, particle shape, and diffusion.
Main Methods:
- Langevin dynamics simulations in three dimensions.
- Systematic variation of propelling force and particle aspect ratio.
- Analysis of diffusion coefficient as a function of obstructed volume fraction.
Main Results:
- Diffusion coefficient shows a non-monotonic concave dependence on obstacle density.
- Enhanced particle diffusivity observed with increasing obstacle concentration.
- Interplay between self-propulsion and particle shape anisotropy drives this enhancement.
Conclusions:
- Particle shape and self-propulsion critically influence diffusion in obstructed environments.
- Regions of monotonic and non-monotonic diffusivity dependence were identified.
- The study elucidates counterintuitive diffusion behaviors in complex systems.
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