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Updated: Jul 13, 2026
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Studying Large Amplitude Oscillatory Shear Response of Soft Materials
Published on: April 25, 2019
Elastic behavior in a supercooled liquid: analysis of viscoelasticity using an extended mode coupling model
Das1
1School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
Summary
Extended mode coupling theory reveals that undercooled liquids support shear waves. Increasing density reduces the minimum wave number, indicating a growing dynamic length scale and a slowing of shear wave propagation.
Area of Science:
- Condensed matter physics
- Theoretical physics
- Statistical mechanics
Background:
- Understanding the dynamics of undercooled liquids is crucial for materials science.
- Shear waves provide insights into the structural relaxation and dynamics of disordered materials.
- Mode coupling theory (MCT) is a key theoretical framework for describing liquid dynamics near the glass transition.
Purpose of the Study:
- To analyze transverse current correlations in undercooled liquids using extended mode coupling theory.
- To investigate the behavior of shear waves and their relationship to density and dynamic length scales.
- To explore the impact of density on the propagation of shear waves and the nature of the mode coupling transition.
Main Methods:
- Application of the extended mode coupling theory formalism.
- Analysis of transverse current correlations.
- Investigation of shear wave properties, including wave number, speed, and wavelength.
Main Results:
- Undercooled liquids sustain shear waves up to a minimum wave number.
- Increasing density leads to a decrease in this minimum wave number, signifying a growing dynamic length scale.
- Shear wave speed diminishes towards zero as a critical wave number is approached.
- Maximum wavelength initially increases towards the mode coupling transition, then grows slower as the transition is truncated.
Conclusions:
- The study elucidates the role of density in modifying shear wave dynamics in undercooled liquids.
- A growing length scale, linked to liquid dynamics, is identified with increasing density.
- The findings provide a deeper understanding of shear wave behavior near the mode coupling transition and its cutoff.
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