Interface stability, interface fluctuations, and the Gibbs-Thomson relationship in motility-induced phase separations

Area of Science:

• Physics
• Soft Matter Physics
• Statistical Mechanics

Background:

• Minimal models of self-propelled particles with volume exclusion interactions show phase separation.
• Motility-induced phase separation (MIPS) is a key phenomenon in active matter systems.

Purpose of the Study:

• To explain interfacial stability and fluctuations in MIPS.
• To demonstrate the validity of the Gibbs-Thomson relationship in MIPS.
• To analyze the late-stage coarsening dynamics of MIPS.

Main Methods:

• Modeling microscopic dynamics of active particles in the interfacial region.
• Analyzing interfacial stability and fluctuations.
• Applying the Gibbs-Thomson relationship.
• Investigating late-stage coarsening dynamics.

Main Results:

• Microscopic dynamics modeling explains interfacial stability and fluctuations in MIPS.
• The Gibbs-Thomson relationship is demonstrated to be valid in MIPS.
• Late-stage coarsening dynamics of MIPS at vanishing supersaturation follow Lifshitz-Slyozov scaling laws.

Conclusions:

• Microscopic modeling provides a robust framework for understanding MIPS phenomena.
• The study bridges the gap between microscopic dynamics and macroscopic thermodynamic principles in active matter.
• Findings offer insights into the fundamental mechanisms governing phase separation in self-propelled particle systems.