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Updated: Jul 11, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Kinetics of ordering in fluctuation-driven first-order transitions: simulation and theory
1College of General Studies, Boston University, Boston, Massachusetts 02140, USA.
Summary
The Brazovskii model describes systems with competing interactions. Numerical simulations confirm its free energy structure, but reveal unstable growth dynamics after deep quenches, challenging nucleation theory.
Area of Science:
- Condensed matter physics
- Statistical mechanics
Background:
- The Brazovskii model describes systems with competing interactions and constraints.
- Its key feature is an isotropic fluctuation spectrum with a maximum at a nonzero wave vector.
- Brazovskii showed fluctuations alter free energy from $\phi^4$ to $\phi^6$, making the disordered state metastable.
Purpose of the Study:
- To numerically verify the $\phi^6$ free energy form predicted by Brazovskii.
- To investigate the dynamics of phase transitions from a disordered to a lamellar state.
- To explore the validity of nucleation theory in deep quench scenarios.
Main Methods:
- Numerical simulations to determine equilibrium free energy.
- Dynamical calculations generalizing Brazovskii's approach.
- Analysis of phase transition dynamics under deep quenches.
Main Results:
- Numerical simulations confirmed the $\phi^6$ form of the equilibrium free energy.
- Dynamics following deep quenches were characterized by unstable growth, not nucleation.
- The disordered state can exhibit prolonged instability after a quench.
Conclusions:
- The study validates the Brazovskii model's free energy predictions.
- It reveals a deviation from nucleation-driven dynamics in deep quenches, favoring unstable growth.
- Prolonged instability of the disordered phase is a significant dynamical outcome.
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