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Published on: November 24, 2016
Heterogeneous nucleation in the low-barrier regime
Benjamin Scheifele1, Ivan Saika-Voivod, Richard K Bowles
1Department of Physics, St. Francis Xavier University, Antigonish, Nova Scotia, Canada B2G 2W5.
Summary
Heterogeneous nucleation in the Ising model is studied. The free energy barrier for nucleation does not vanish at the limit of stability, contrary to expectations.
Area of Science:
- Statistical mechanics
- Condensed matter physics
Background:
- The two-dimensional Ising model is a fundamental model in statistical mechanics.
- Heterogeneous nucleation is a critical process in phase transitions.
- Understanding nucleation barriers is essential for predicting transition rates.
Purpose of the Study:
- To investigate heterogeneous nucleation in the 2D Ising model induced by a line impurity.
- To determine the behavior of the free energy barrier near the limit of stability.
- To validate nucleation theory predictions against simulation results.
Main Methods:
- Simulations of the two-dimensional Ising model.
- Introduction of a line of fixed spins as an impurity.
- Calculation of the free energy barrier for nucleation.
- Comparison with transition state theory and the nucleation theorem.
Main Results:
- A limit of stability was identified as the impurity size increased.
- The free energy barrier for nucleation did not vanish at this limit.
- Predictions for nucleation time and critical cluster size agreed well with simulations.
Conclusions:
- The free energy barrier's behavior near the limit of stability differs from some theoretical expectations.
- The study validates the accuracy of transition state theory and the nucleation theorem.
- Simulation results provide valuable insights into heterogeneous nucleation phenomena.
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