What is the Curie temperature and what does it measure?
The Curie temperature refers to the point at which materials lose their ferromagnetism, which in turn describes the ability of a material to align its own atoms even in the absence of a magnetic field. At this point, a material becomes paramagnetic and needs an external magnetic field to become magnetized again and stay in that state. The Curie temperature phenomenon was named after the researcher Pierre Curie. Magnetic materials can change their properties at a wide range of temperatures, although these often have to be quite high. When the temperature drops again, the material regains its magnetism, which shows that this phase change is reversible.