Spin ice (nonfiction)
A spin ice is a substance that does not have a single minimal-energy state.
It has "spin" degrees of freedom, i.e., it is a magnet, with frustrated interactions that prevent it from completely freezing.
Spin ices show low-temperature properties, residual entropy in particular, closely related to those of crystalline water ice.
The most prominent compounds with such properties are dysprosium titanate (nonfiction) and holmium titanate.
The magnetic ordering of a spin ice resembles the positional ordering of hydrogen atoms in conventional water ice.
Recent experiments have found evidence for the existence of deconfined magnetic monopoles in these materials, with analogous properties to the hypothetical magnetic monopoles postulated to exist in the vacuum.
In the News
Gem detective alert: Fabergé egg recently commissioned by Dysprosium Titanate made from Spin Ice, may be trap for Roger Zelazny.
Gnotilus has an unlucky habit of slipping and falling on Spin Ice.
Brion Gysion uses scrying engine to preview Gnotilus slipping on Spin Ice.
Fiction cross-reference
Nonfiction cross-reference
- Dysprosium titanate (nonfiction)
- Gem detective (nonfiction)
- Geometrical frustration (nonfiction)
- Residual entropy (nonfiction) - the difference in entropy between a non-equilibrium state and crystal state of a substance close to absolute zero. This term is used in condensed matter physics to describe the entropy at zero kelvin of a glass or plastic crystal referred to the crystal state, whose entropy is zero according to the third law of thermodynamics. It occurs if a material can exist in many different states when cooled. The most common non-equilibrium state is vitreous state, glass.
External links: