Anisotropy and spiral organizing centers in patterned excitable media

Area of Science:

• Chemical kinetics and reaction-diffusion systems
• Nonlinear dynamics and complex systems

Background:

• The Belousov-Zhabotinsky reaction is a classic example of an oscillating chemical reaction exhibiting wave propagation.
• Understanding wave dynamics in excitable media is crucial for various fields, including biology and materials science.
• Previous studies often focused on homogeneous or predefined patterned media.

Purpose of the Study:

• To investigate chemical wave behavior in a spatially patterned Belousov-Zhabotinsky system.
• To explore the impact of engineered catalyst inhomogeneities on wave propagation dynamics.
• To demonstrate a flexible experimental approach for creating custom excitable media.

Main Methods:

• Utilizing an inkjet printer to deposit the catalyst onto membranes, creating specific spatial patterns.
• Observing and analyzing the propagation of chemical waves within the patterned reaction-diffusion system.
• Characterizing the resulting wave geometries and propagation anisotropy.

Main Results:

• Cellular inhomogeneities induced global anisotropy in wave propagation.
• Specific local catalyst patterns led to the formation of hexagonal, diamond, and pentagonal wave geometries.
• Spontaneous emergence of spiral wave sources acting as organizing centers for wave activity.

Conclusions:

• Inkjet printing provides a versatile method for fabricating patterned excitable media.
• Engineered spatial inhomogeneities significantly influence chemical wave dynamics and pattern formation.
• This approach enables the study of complex wave behaviors in customizable reaction-diffusion systems.