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Vortex Pattern Stabilization in Thin Films Resulting from Shear Thickening of Active Suspensions
Henning Reinken1, Andreas M Menzel1
1Institut für Physik, Otto-von-Guericke-Universität Magdeburg, Universitätsplatz 2, 39106 Magdeburg, Germany.
Physical Review Letters
|April 13, 2024
Summary
Active microswimmers in shear-thickening fluids self-organize into stable vortex patterns. This novel approach enables precise micrometer-scale structuring for applications like thin films and membranes.
Area of Science:
- Physics
- Materials Science
- Soft Matter Physics
Background:
- Structuring materials on the micrometer scale is crucial for advanced applications, including phononic devices.
- Active turbulence in microswimmer suspensions typically leads to disordered states.
Purpose of the Study:
- To develop a novel method for achieving regular, micrometer-scale structuring in active suspensions.
- To explore the self-organization of active matter within shear-thickening fluids.
Main Methods:
- Utilizing a shear-thickening carrier fluid containing active microswimmers.
- Observing the self-organization of the fluid into stable vortex patterns.
- Introducing passive particles of intermediate size to study their spatial organization.
Main Results:
- Active turbulence in shear-thickening fluids intrinsically stabilizes regular vortex patterns.
- The active suspension self-organizes into a periodic, nonequilibrium structured state.
- Passive particles are spatially organized by the emergent fluid structures.
Conclusions:
- This approach offers a new route for functionalization via patterning of thin films and membranes.
- The self-organization phenomenon provides a pathway to controlled micrometer-scale structuring.
- Leveraging active turbulence in specific fluids enables predictable material organization.
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