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Sputter Growth and Characterization of Metamagnetic B2-ordered FeRh Epilayers
Published on: October 6, 2013
Phase transition versus disorder: A criterion derived from a two-dimensional dynamic ferromagnetic model
1Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742.
Summary
Rapidly cooling the two-dimensional Ising model can prevent spin ordering. Under specific hyperbolic cooling, the system freezes into a disordered state due to insufficient time for ordering effects to manifest.
Area of Science:
- Statistical mechanics
- Condensed matter physics
Background:
- The two-dimensional Ising model describes magnetic materials.
- Understanding spin dynamics under rapid temperature changes is crucial.
Purpose of the Study:
- To investigate spin correlation functions in a 2D Ising model under rapid cooling.
- To analyze the impact of hyperbolic cooling on system ordering.
Main Methods:
- Solving dynamical equations for spin correlation functions.
- Applying a hyperbolic cooling schedule: T(-1) = T(0) (-1) + bt.
- Analyzing the system's behavior for large cooling constants (b).
Main Results:
- For large b, the ordering term in dynamical equations becomes ineffective.
- The system freezes into a disordered state during rapid quenches.
- Correlation length is determined by random walker diffusion distance during cooling.
Conclusions:
- Rapid hyperbolic cooling can suppress order in the 2D Ising model.
- The rate of cooling significantly impacts the final state of the system.
- The correlation length provides a measure of disorder in quenched systems.
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