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Updated: May 22, 2026
09:32
Cooling Rate Dependent Ellipsometry Measurements to Determine the Dynamics of Thin Glassy Films
Published on: January 26, 2016
Ideal glass transitions by random pinning.
Chiara Cammarota1, Giulio Biroli
1Institut de Physique Théorique, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), and Centre National de la Recherche Scientifique (CNRS) Unité de Recherche Associée 2306, 91191 Gif-sur-Yvette, France. chiara.cammarota@cea.fr
Summary
Pinning a fraction of particles in supercooled liquids induces an ideal glass transition. This study reveals critical properties and links frozen particle distance to liquid structure, offering new insights into glass transition theories.
Area of Science:
- Condensed Matter Physics
- Statistical Mechanics
- Materials Science
Background:
- Supercooled liquids exhibit complex dynamics near the glass transition.
- Understanding the mechanisms of glass formation is a key challenge in condensed matter physics.
Purpose of the Study:
- To investigate the effect of freezing a fraction of particles on the glass transition in supercooled liquids.
- To explore the theoretical framework of random first-order transition theory in the context of particle pinning.
- To analyze the critical properties and length/time scales associated with this induced glass transition.
Main Methods:
- Mean-field approximations to derive the phase diagram in the temperature-fraction plane.
- Real-space renormalization group method to determine critical properties.
- Analysis of the relationship between frozen particle distance and the point-to-set length scale.
Main Results:
- An ideal glass transition is induced by pinning particles at a critical fraction c(K)(T).
- Critical properties, including diverging length and time scales, are determined near the transition.
- The distance between pinned particles relates to the static point-to-set length scale of the unconstrained liquid.
Conclusions:
- Particle freezing provides a novel route to induce and study glass transitions.
- This method offers a promising avenue for testing theories of the glassy state.
- Differences in freezing geometries and configurations are discussed, highlighting the importance of equilibrium starting points.
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