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Force Distributions near Jamming and Glass Transitions
1Department of Chemistry and Biochemistry, University of California at Los Angeles, Los Angeles, California 90095-1569 and James Franck Institute, The University of Chicago, Chicago, Illinois 60637.
Physical Review Letters
|January 3, 2001
Summary
Researchers studied interparticle forces near glass and jamming transitions. A force peak indicates yield stress, sensitive to temperature, shear stress, and density, supporting a generalized jamming phase diagram.
Area of Science:
- Soft matter physics
- Statistical mechanics
Background:
- Supercooled liquids and foams exhibit complex behaviors near phase transitions.
- Understanding interparticle forces is crucial for characterizing these states.
Purpose of the Study:
- To calculate the distribution of interparticle normal forces P(F) near glass and jamming transitions.
- To investigate the relationship between P(F) and macroscopic properties like yield stress.
- To evaluate the validity of a generalized jamming phase diagram.
Main Methods:
- Computational modeling of supercooled liquids and foams.
- Analysis of interparticle normal force distributions P(F).
Main Results:
- P(F) develops a peak near glass and jamming transitions.
- The peak's height correlates with decreasing temperature, decreasing shear stress, and increasing packing density.
- Observed P(F) shape is consistent with experimental data from granular packings.
Conclusions:
- The emergence of the P(F) peak signals the development of a yield stress.
- The peak's sensitivity to external parameters supports the generalized jamming phase diagram.
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