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Topological Stabilization and Dynamics of Self-Propelling Nematic Shells
Babak Vajdi Hokmabad1,2, Kyle A Baldwin1,3, Carsten Krüger1
1Max Planck Institute for Dynamics and Self-Organization, Am Faßberg 17, 37077 Göttingen, Germany.
Physical Review Letters
|November 9, 2019
Summary
We stabilized self-propelling liquid shells using soft topological constraints, preventing rupture and enabling controlled motion. Anisotropic elasticity counterbalances viscous drag, allowing for dynamic control of these novel liquid-shell micromachines.
Area of Science:
- Soft matter physics
- Microfluidics
- Materials science
Background:
- Liquid shells (e.g., vesicles) are prone to instability and rupture.
- Designing stable, motile liquid-shell micromachines is challenging due to mechanical equilibrium issues.
Purpose of the Study:
- To develop controllable, self-propelling liquid shells.
- To stabilize these shells against interfacial instability and rupturing.
- To understand and control their propulsion dynamics.
Main Methods:
- Stabilization using soft topological constraints from a nematogen oil.
- Experimental and simulation-based analysis of shell behavior.
- Investigation of anisotropic elasticity and viscous drag effects.
Main Results:
- Demonstrated stabilization of liquid shells via topological constraints.
- Showed anisotropic elasticity counterbalances viscous drag, preventing rupture.
- Identified meandering propulsion driven by broken symmetries.
- Established routes for motion control through topology, chemical signaling, and hydrodynamics.
Conclusions:
- Controllable self-propelling liquid shells can be designed using soft topological constraints.
- Anisotropic elasticity is key to overcoming destabilizing forces and ensuring shell integrity.
- Understanding symmetry breaking provides pathways for precise control of micromachine locomotion.
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