Spiral diffusion of rotating self-propellers with stochastic perturbation

Area of Science:

• Physics, Soft Matter
• Microscopic Systems
• Statistical Mechanics

Background:

• Translational diffusion in microscopic systems is understood, but its evolution based on initial conditions is less explored.
• The interplay between orientational diffusion and powered motion creates complex behaviors at small scales.

Purpose of the Study:

• To develop a theoretical framework for the spiral motion of mean trajectories in microscopic powered systems.
• To investigate the influence of propulsion speed, angular velocity, orientational diffusion, and chirality reversal on trajectory evolution.
• To demonstrate the experimental feasibility of observing this phenomenon.

Main Methods:

• Theoretical modeling of particle trajectories incorporating rotational and translational dynamics.
• Experimental validation using microscale rotating motors, specifically tadpole-like and Janus sphere dimers.
• Analysis of trajectory sensitivity to key kinematic parameters.

Main Results:

• A theory predicting spiral motion of the mean trajectory was established.
• Experimental results confirmed the theoretical predictions for micro-motor behavior.
• The mean trajectory was shown to be sensitive to propulsion speed, angular velocity, and diffusion rates.

Conclusions:

• The spiral motion of microscopic powered particles is a theoretically sound and experimentally observable phenomenon.
• The sensitivity of the trajectory to kinematic parameters provides a potential method for their precise determination.
• This work offers new insights into the dynamics of active microscale systems.