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Updated: Jun 28, 2026
12:26
Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
Published on: August 27, 2013
Statistics and morphologies of stable droplets in scalar active fluids
Kathrin Hertäg1, Joshua F Robinson2,3, Thomas Speck1
1University of Stuttgart, Institute for Theoretical Physics IV, Heisenbergstr. 3, 70569 Stuttgart, Germany.
Physical Review. E
|February 20, 2026
Summary
Active Model B+ allows for stable coexistence of many finite droplets, unlike conventional phase segregation. This study numerically explores the transition from single to multiple droplet systems, finding good agreement with theory and a key parameter governing droplet properties.
Area of Science:
- Soft matter physics
- Statistical mechanics
- Computational physics
Background:
- Conventional phase segregation minimizes interfacial area, leading to single droplets.
- Active Model B+ introduces nonpotential terms, enabling stable coexistence of multiple finite droplets.
Purpose of the Study:
- Numerically investigate Active Model B+ near the macrophase to microphase segregation transition.
- Analyze the transition from single droplet to multiple droplet systems.
- Characterize droplet properties and identify new transitions.
Main Methods:
- Numerical simulations of Active Model B+.
- Analysis of droplet number, density, and fractal dimension.
- Investigation of transitions between segregation regimes.
Main Results:
- Noise influences phase transitions but agreement with mean-field theory is strong.
- A single parameter correlates droplet properties like number, density, and fractal dimension.
- A transition to a hexagonal lattice of regular droplets is observed deeper in microphase segregation.
Conclusions:
- Active Model B+ successfully models systems with multiple stable droplets.
- The study provides a detailed understanding of the transition dynamics and droplet characteristics.
- A novel hexagonal lattice phase is identified within the microphase segregation regime.
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