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Workshop on Amorphous Solids, Hong Kong,
September 2008
Lecture 1: Introduction to glasses
Itamar Procaccia
Institute of Theoretical Physics
Chinese University of Hong Kong
Glasses: disordered materials that lack the periodicity of crystals but behave mechanically
like solids.
•Created by cooling a liquid “fast enough” to avoid crystallization. (Known for millennia).
•The glassy state is ubiquitous in nature. (Obsidian, window glass, fiber optics, plastics, metallic glasses and alloys, etc. etc.)
•Our aim is to understand the molecular processes by which liquids acquire amorphous rigidity.
•We will try to understand simple models in great detail.
Typical phase diagram:
Some experimentalexamples
The TTT-diagram
Slowing down
The stretched exponential approximation:
The Vogel-Fulcher fit
Experimental methodsBroad Band Dielectric Spectroscopy (BDS)
A nice riddle:
Specific heat spectroscopy
The energy landscape picture
Mechanical Properties
Monte Carlo: