Spiral defect drift in the wave fields of multiple excitation patterns

Area of Science:

• Nonlinear dynamics
• Chemical kinetics
• Excitable media

Background:

• Spiral waves are complex spatiotemporal patterns observed in various excitable systems.
• Forcing excitable media with wave trains can alter spiral wave behavior.
• Understanding defect dynamics is crucial for controlling patterns in these systems.

Purpose of the Study:

• To investigate the drift behavior of defects in excitable systems under high-frequency wave train forcing.
• To analyze the relationship between wave frequency and defect drift velocity.
• To explore methods for controlling defect position using multiple wave fields.

Main Methods:

• Utilized the Barkley model, a mathematical model for excitable media.
• Simulated planar and circular wave trains with varying frequencies.
• Analyzed defect trajectories and velocities in response to forcing parameters.

Main Results:

• Spiral waves decay to drifting defects when subjected to high-frequency wave trains.
• Defect drift velocity in planar wave trains is dependent on wave frequency.
• Two circular wave fields induce defect drift perpendicular to the pacemaker axis, with direction dependent on frequency and initial position.
• Three circular wave fields enable precise defect positioning near the center of the pacemaker triangle.

Conclusions:

• The drift of defects in excitable systems can be controlled by external wave train forcing.
• The Barkley model accurately predicts defect dynamics observed in experiments.
• Precise control over defect positioning is achievable using specific configurations of circular wave fields, with implications for pattern formation in excitable media.