Related Experiment Videos
Theory of aging in structural glasses
Vassiliy Lubchenko1, Peter G Wolynes
1Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla 92093-0371, USA.
The Journal of Chemical Physics
|August 5, 2004
Summary
This study extends the random first-order transition theory to aging in structural glasses, introducing a new model for energy landscapes. The theory quantitatively explains glassy relaxation, predicts ultraslow dynamics, and correlates nonlinearity with liquid fragility.
Area of Science:
- Condensed matter physics
- Materials science
- Statistical mechanics
Background:
- Supercooled liquids exhibit complex dynamics and aging phenomena.
- Nonequilibrium structural glasses present challenges for theoretical modeling.
- Existing theories like random first-order transition theory provide a basis for understanding liquid dynamics.
Purpose of the Study:
- To extend the random first-order transition theory to aging in nonequilibrium structural glasses.
- To introduce a new theoretical framework based on local energy landscapes.
- To provide a unified treatment of supercooled liquid and glassy regimes.
Main Methods:
- Reformulation of "entropic droplets" using libraries of local energy landscapes.
- Microscopic theory of aging developed from first principles.
- Comparison and deviation analysis with established formalisms (Narayanaswamy-Moynihan-Tool, Adam-Gibbs).
Main Results:
- Quantitative correlation between glassy relaxation nonlinearity and liquid fragility.
- Explanation for non-Arrhenius temperature dependence in quenched glasses.
- Quantitative prediction of relaxation spectra broadening and spatially fluctuating fictive temperatures with non-Gaussian statistics.
Conclusions:
- The developed theory uniformly treats supercooled liquids and glasses.
- Deviations from existing models are predicted and experimentally validated.
- The theory predicts ultraslow relaxations in deeply quenched glasses due to fluctuating fictive temperatures.