Rectification of self-propelled particles by symmetric barriers

Area of Science:

• Physics of self-propelled particles
• Statistical mechanics
• Soft matter physics

Background:

• Periodic potentials and asymmetric barriers rectify particle motion.
• Self-propelled particle dynamics are influenced by external potentials and propulsion characteristics.

Purpose of the Study:

• To investigate inducing directed motion in symmetric potentials by modulating self-propulsion.
• To analyze the effects of phase-shifted, modulated propulsion on particle drift.
• To explore the impact of asymmetric barriers on modulated propulsion-induced drift.

Main Methods:

• Analytical determination of mean drift in the adiabatic limit of slow rotational diffusion.
• Theoretical analysis of particle dynamics under modulated self-propulsion and periodic potentials.
• Investigation of temperature effects on particle drift.

Main Results:

• A nonzero average drift can be induced in symmetric potentials by phase-shifting modulated self-propulsion velocity.
• The mean drift is analytically determined in the adiabatic limit, showing temperature dependence.
• Modulating self-propulsion significantly enhances or reverses drift in asymmetric potentials.

Conclusions:

• Periodic potentials with symmetric barriers can induce directed motion via modulated self-propulsion.
• Phase-shifting the propulsion modulation relative to the potential is key for inducing drift.
• This work provides a mechanism for controlling self-propelled particle transport in tunable potentials.