Effect of shear on persistence in coarsening systems
1School of Physics and Astronomy, The University, Oxford Road, Manchester M13 9PL, United Kingdom.
Summary
We analytically studied how uniform shear flow affects coarsening systems. The anisotropic Ohta-Jasnow-Kawasaki (OJK) approximation revealed new persistence exponents in 2D and 3D, with shear impacting autocorrelation in 3D.
Area of Science:
- Physics
- Statistical Mechanics
- Soft Matter
Background:
- Coarsening systems exhibit domain growth over time.
- Persistence properties describe the temporal behavior of these systems.
- Shear flow can significantly alter system dynamics.
Purpose of the Study:
- To investigate the impact of uniform shear flow on the persistence properties of coarsening systems.
- To determine the persistence exponent (theta) and autocorrelation exponent (lambda) under shear.
- To analyze these effects in different spatial dimensions (d=2 and d=3).
Main Methods:
- Analytical study using the anisotropic Ohta-Jasnow-Kawasaki (OJK) approximation.
- Focus on systems with a nonconserved scalar order parameter.
- Calculation of persistence and autocorrelation exponents.
Main Results:
- Derived nontrivial persistence exponents: theta = 0.5034 in d=3 and theta = 0.2406 in d=2.
- The persistence exponent in d=2 is double the value for unsheared systems in d=1.
- The autocorrelation exponent (lambda) is affected by shear in d=3 but not in d=2.
Conclusions:
- Uniform shear flow introduces significant changes to the persistence properties of coarsening systems.
- The anisotropic OJK approximation provides a valuable framework for understanding shear effects.
- Dimensionality plays a crucial role in how shear influences system dynamics and exponents.
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