Electrophoresis of active Janus particles

Area of Science:

• Theoretical physics
• Soft matter physics
• Active matter dynamics

Background:

• Active Janus motors are self-propelled particles with distinct surface properties.
• External fields can influence the motion of micro- and nanomachines.
• Understanding directed motion is crucial for applications in targeted delivery and micro-robotics.

Purpose of the Study:

• To theoretically investigate the dynamics of a self-propelled active Janus motor in an external electric field.
• To analyze how an electric field can control the trajectory of a Janus particle towards specific targets.
• To elucidate the relationship between surface activity, electric field strength, and particle orientation.

Main Methods:

• Theoretical modeling of active Janus motor dynamics.
• Application of a perturbative scheme to analyze particle trajectory.
• Analysis of orientational dynamics under leading-order approximations.

Main Results:

• The external electric field can effectively manipulate the movement of the Janus motor.
• The orientational dynamics of the Janus particle are analogous to a mathematical pendulum.
• Angular velocity is sensitive to both the electric field strength and the particle's surface activity.

Conclusions:

• Electric fields offer a viable method for directing active Janus motors.
• The pendulum analogy provides a simplified yet effective model for understanding motor orientation.
• Control over motor trajectory is achievable by tuning electric field and surface activity parameters.