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Controlling crystal symmetries in phase-field crystal models
Kuo-An Wu1, Mathis Plapp, Peter W Voorhees
1Department of Materials Science and Engineering, Northwestern University, Evanston, IL 60208, USA. kuoan-wu@northwestern.edu
Summary
Researchers control crystal symmetries in phase-field models using nonlinear resonances. They achieved square and square-hexagon coexistence, but square-liquid coexistence requires careful tuning for materials simulations.
Area of Science:
- Computational materials science
- Condensed matter physics
- Mathematical modeling
Background:
- Phase-field crystal (PFC) models describe materials at atomic scales.
- Controlling symmetry in ordered states is crucial for materials design.
- Nonlinear resonances offer a potential mechanism for symmetry control.
Purpose of the Study:
- To investigate controlling ordered state symmetry in 2D PFC models via nonlinear resonances.
- To develop a general method for constructing free energy functionals for controlled solid-liquid coexistence.
- To demonstrate square-liquid coexistence in a 2D PFC model.
Main Methods:
- Tuning nonlinear resonances within PFC models.
- Developing and analyzing free energy functionals.
- Systematic parameter analysis for nonlinear terms.
Main Results:
- Achieved control over square symmetry and square-hexagon coexistence.
- Demonstrated the difficulty in obtaining square-liquid coexistence.
- Developed a general method for constructing free energy functionals for desired symmetries.
- Provided a specific functional for square-liquid coexistence.
Conclusions:
- Nonlinear resonances provide a pathway to control crystal symmetries in PFC models.
- The developed method facilitates the creation of free energy functionals for specific solid-liquid coexistence scenarios.
- Findings have implications for simulating materials with simple cubic symmetry.
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