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Updated: Jun 23, 2026
09:41
Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides
Published on: May 29, 2018
Kinetics of phase separation in thin films: lattice versus continuum models for solid binary mixtures.
Subir K Das1, Jürgen Horbach, Kurt Binder
1Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064, India.
Summary
This study models phase separation kinetics in thin solid binary mixtures using a kinetic Ising model. It reveals how wetting layers and lateral separation lead to domain growth following the Lifshitz-Slyozov law.
Area of Science:
- Materials Science
- Physical Chemistry
- Statistical Mechanics
Background:
- Understanding phase separation kinetics is crucial for designing materials with specific properties.
- Thin film geometries present unique challenges due to surface and confinement effects.
Purpose of the Study:
- To describe phase separation kinetics in solid binary mixtures within thin film geometry.
- To investigate the interplay between wetting layer formation and lateral phase separation.
- To provide a model valid across a wide temperature range, including far below the critical point.
Main Methods:
- Utilizing the Kawasaki spin-exchange kinetic Ising model.
- Employing a discrete lattice molecular field formulation.
- Analyzing domain size evolution and its dependence on time and temperature.
Main Results:
- The model successfully describes the interplay of wetting and lateral phase separation.
- Characteristic domain size grows with time according to the Lifshitz-Slyozov t{1/3} law.
- The formulation is accurate even far below the critical point, unlike Ginzburg-Landau models.
Conclusions:
- The presented kinetic Ising model offers a robust framework for studying phase separation in thin films.
- It provides transparent relations between interaction parameters and observable phenomena.
- The model ensures consistency between free energy and time evolution, especially at low temperatures.
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