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Shape Switching and Tunable Oscillations of Adaptive Droplets
Tim Dullweber1,2, Roman Belousov1, Camilla Autorino1,3
1European Molecular Biology Laboratory, Heidelberg, Germany.
Physical Review Letters
|October 5, 2025
Summary
Living materials with responsive interfaces exhibit shape bistability and oscillations, revealing new physical signal processing mechanisms. These findings are observed in soft active materials and zebrafish embryo development.
Area of Science:
- Physics, Materials Science, Developmental Biology
Background:
- Living materials dynamically adapt shape in response to environmental signals.
- The role of shape adaptation in signal processing and feedback within these materials is not well understood.
Purpose of the Study:
- To investigate how shape changes in soft active materials influence signal processing and feedback dynamics.
- To explore novel mechanisms of physical signal processing through shape adaptation.
Main Methods:
- Theoretical modeling of droplets with signal-responsive interfacial tensions.
- Analysis of critical points and associated dynamics (bistability, excitability, oscillations).
- Comparison with experimental data from zebrafish embryos.
Main Results:
- Droplets with signal-responsive interfacial tensions demonstrate shape bistability, excitable dynamics, and oscillations.
- Identification of critical points as key to physical signal processing via shape adaptation.
- Observed critical point signatures in zebrafish embryo boundary formation.
Conclusions:
- Shape adaptation in soft active materials provides novel mechanisms for physical signal processing.
- Critical points play a significant role in the dynamic behavior and signal processing capabilities of these materials.
- The findings have implications for understanding developmental processes like boundary formation in biological systems.
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