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Updated: Jul 3, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Aging and relaxation in glass-forming systems
Valery Ilyin1, Itamar Procaccia, Ido Regev
1Department of Chemical Physics, The Weizmann Institute of Science, Rehovot, Israel.
Summary
Glass-forming systems exhibit competing states that form ordered patches upon cooling. Relaxation events occur in low-modulus regions between these patches, driving aging and structural changes without a singular crisis at finite temperatures.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Physical Chemistry
Background:
- Glass-forming systems are characterized by slow dynamics and aging upon cooling.
- Existing theories like Adam-Gibbs and Vogel-Fulcher predict a singular crisis (infinite relaxation time) at a finite temperature.
Purpose of the Study:
- To propose a new generic mechanism for aging and dynamics in glass-forming systems.
- To relate structural properties (competing states, local order) to dynamic processes (relaxation, plasticity).
- To challenge the prediction of a singular crisis at finite temperatures.
Main Methods:
- Theoretical modeling of glass-forming systems with competing states.
- Analysis of local shear modulus and its relation to relaxation events.
- Examination of aging as localized transitions between potential energy minima.
Main Results:
- Identified competing states locally close in energy to the ground state.
- Demonstrated that aging occurs in low-shear-modulus regions between ordered patches.
- Showed aging events are localized transitions, increasing patch size and slowing dynamics.
- Proposed dynamics are linked to the reduction of liquid-like amorphous material volume.
Conclusions:
- Glass-forming system dynamics arise from competing states and localized relaxation events.
- Aging is a consequence of transitions in low-modulus regions, leading to increased local order.
- The proposed model suggests a superexponential increase in relaxation time and correlation length, not a singular crisis at finite temperatures.
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