Related Experiment Video
Updated: Apr 5, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
8.7K
Spontaneous energy-barrier formation in entropy-driven glassy dynamics
Chiara Cammarota1, Enzo Marinari2
1Sapienza, University of Rome P.le Aldo Moro 2, I-00185 Rome, Italy.
Summary
We present a new model for understanding how glassy systems relax. This model reveals a simple aging behavior in the activated relaxation process, even with complex energy landscapes.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Computational Physics
Background:
- Describing activated relaxation in glassy systems within multidimensional configurational space is a persistent challenge.
- Understanding the out-of-equilibrium dynamics of glasses is crucial for materials science.
Purpose of the Study:
- To develop a phenomenological description for the activated relaxation of glassy systems.
- To analyze the out-of-equilibrium dynamics of a model with a rough potential energy landscape.
Main Methods:
- Numerical and analytical analysis of a model with a rough potential energy landscape.
- Investigation of dynamics involving finite-potential energy barriers and less energy-demanding escaping paths.
Main Results:
- The model exhibits dynamics where relaxation occurs over finite-potential energy barriers, despite easier escape routes.
- Dynamical paths episodically reach a high-fixed-threshold energy, leading to a simple thermally activated aging phenomenology.
- A novel description of dynamics using spontaneously emerging dynamical basins was introduced.
Conclusions:
- The developed phenomenological model provides insights into the activated relaxation of glassy systems.
- The findings are expected to be relevant for realistic models of glass-formers in the thermally activated regime.
- The concept of spontaneously emerging dynamical basins offers a new perspective on glass dynamics.
Related Concept Videos
02:39Entropy
38.1K
Salt particles that have dissolved in water never spontaneously come back together in solution to reform solid particles. Moreover, a gas that has expanded in a vacuum remains dispersed and never spontaneously reassembles. The unidirectional nature of these phenomena is the result of a thermodynamic state function called entropy (S). Entropy is the measure of the extent to which the energy is dispersed throughout a system, or in other words, it is proportional to the degree of disorder of a...
38.1K
01:18Entropy
3.8K
The first law of thermodynamics is quantitatively formulated via an equation relating the internal energy of a system, the heat exchanged by it, and the work done on it. A quantitative formulation of the second law of thermodynamics leads to defining a state function, the entropy.
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
When an ideal gas expands isothermally, the disorder in the gas increases. From the molecular perspective, the gas molecules have more volume to move around in.
Consider an infinitesimal step in the expansion, which...
3.8K
01:14The Second Law of Thermodynamics
7.2K
In the quest to identify a property that may reliably predict the spontaneity of a process, a promising candidate has been identified: entropy. Scientists refer to the measure of randomness or disorder within a system as entropy. High entropy means high disorder and low energy. To better understand entropy, think of a student’s bedroom. If no energy or work were put into it, the room would quickly become messy. It would exist in a very disordered state, one of high entropy. Energy must be...
7.2K
02:39Gibbs Free Energy
41.3K
One of the challenges of using the second law of thermodynamics to determine if a process is spontaneous is that it requires measurements of the entropy change for the system and the entropy change for the surroundings. An alternative approach involving a new thermodynamic property defined in terms of system properties only was introduced in the late nineteenth century by American mathematician Josiah Willard Gibbs. This new property is called the Gibbs free energy (G) (or simply the free...
41.3K
02:49Second Law of Thermodynamics
28.5K
In the quest to identify a property that may reliably predict the spontaneity of a process, a promising candidate has been identified: entropy. Processes that involve an increase in entropy of the system (ΔS > 0) are very often spontaneous; however, examples to the contrary are plentiful. By expanding consideration of entropy changes to include the surroundings, a significant conclusion regarding the relation between this property and spontaneity may be reached. In thermodynamic models, the...
28.5K
00:53Second Law of Thermodynamics
70.5K
The Second Law of Thermodynamics states that entropy, or the amount of disorder in a system, increases each time energy is transferred or transformed. Each energy transfer results in a certain amount of energy that is lost—usually in the form of heat—that increases the disorder of the surroundings. This can also be demonstrated in a classic food web. Herbivores harvest chemical energy from plants and release heat and carbon dioxide into the environment. Carnivores harvest the...
70.5K