Superheated Solids
Why it Matters?
Gold was found to remain solid even when superheated to 14 times its melting point, challenging long-held beliefs about entropy limits in solids.
What You Should Know?
Superheating refers to a state where a material remains solid even above its melting point.
This phenomenon occurs only if the material is heated rapidly enough to avoid phase transition.
Gold was found to remain solid at 14 times its melting point when exposed to ultrashort laser pulses.
(Gold was heated many times beyond its melting point.)
The material retained its crystalline atomic structure for a few trillionths of a second.
The finding challenges the concept of “entropy catastrophe”, which says solids must melt beyond 3 times their melting point due to disorder.
Entropy catastrophe implies a solid can't have more entropy than its liquid, violating the second law of thermodynamics.
Technique used: Ultrashort laser heating followed by X-ray scattering to detect atomic arrangement.
Applications: Can help develop materials for extreme environments like space, reactors, or re-entry systems.