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Updated: Jun 11, 2025
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Activity-induced phase transition and coarsening dynamics in dry apolar active nematics
Arpan Sinha1,2, Debasish Chaudhuri1,2
1Institute of Physics, Sachivalaya Marg, Bhubaneswar 751005, India. arpan.s@iopb.res.in.
Soft Matter
|October 2, 2024
Summary
This study maps the phase diagram of active nematic systems, revealing a first-order transition driven by density fluctuations and giant fluctuations in the nematic phase. These findings are crucial for understanding active matter dynamics.
Area of Science:
- Soft Matter Physics
- Active Matter Systems
- Statistical Mechanics
Background:
- Active nematic systems exhibit complex behaviors driven by self-propelled particles.
- Understanding phase transitions and fluctuations is key to characterizing these systems.
- Reciprocal interactions play a significant role in the collective dynamics of active matter.
Purpose of the Study:
- To construct a comprehensive phase diagram for a dry, apolar, active nematic system.
- To investigate the nature of the nematic-isotropic transition and associated phase separation.
- To analyze the influence of activity and orientational noise on system phases.
Main Methods:
- Stochastic off-lattice dynamics simulations were employed.
- Mean-field analysis and hydrodynamic theory were utilized.
- The Lebwohl-Lasher interaction model was applied for reciprocal local alignment.
Main Results:
- A first-order nematic-isotropic transition was identified, coupled with fluctuation-dominated phase separation.
- Three distinct phases were mapped: homogeneous isotropic, nematic with giant density fluctuations, and coexistence.
- Reciprocal interactions were shown to induce a density fluctuation-driven first-order transition.
Conclusions:
- The derived phase boundary aligns with numerical simulation results.
- Quenching experiments show nematic ordering precedes particle clustering during coarsening.
- Nematic and density fields exhibit similar scaling behaviors with dynamic exponents near 2.5.
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