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Probing shear-induced rearrangements in Fourier space. II. Differential dynamic microscopy
1L2C, Univ Montpellier, CNRS, Montpellier, France. aime@seas.harvard.edu.
Soft Matter
|December 5, 2018
Summary
Differential Dynamic Microscopy (DDM) under shear provides insights into soft matter dynamics. This study details methods to separate affine and non-affine displacements, crucial for understanding material properties.
Area of Science:
- Soft Matter Physics
- Rheology
- Microscopy
Background:
- Understanding the relationship between mechanical properties and microscopic dynamics is key in soft matter.
- Previous work has explored coupling Fourier-space measurements with rheological tests.
Purpose of the Study:
- To focus on Differential Dynamic Microscopy (DDM) under shear in soft matter.
- To provide a theoretical framework and practical guidelines for analyzing DDM data under shear.
- To differentiate between affine and non-affine contributions to microscopic displacements.
Main Methods:
- Coupling Differential Dynamic Microscopy (DDM) with rheological testing.
- Developing a theoretical approach to analyze DDM data under shear.
- Investigating the role of illumination coherence in DDM.
Main Results:
- Analogies and differences between DDM and dynamic light scattering under shear were identified.
- A method to separate affine and non-affine displacements in DDM was established.
- The coherence of the light source was shown to determine the probed sample thickness in DDM under shear.
Conclusions:
- DDM under shear is a valuable tool for probing soft matter dynamics.
- The developed methods allow for a more detailed understanding of microscopic motion in sheared soft materials.
- Experimental validation on 2D samples and 3D gels supports the theoretical findings.
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