Néel, Louis Eugène Félix (1904–2000)

French physicist who was awarded the Nobel Prize for Physics in 1970 for his work on the magnetic properties of solids and his prediction of the existence of antiferromagnetism, a form of magnetism.

In antiferromagnetic materials, the molecular magnets are arranged in alternate directions and exhibit a very low magnetic susceptibility that increases with temperature. Above a certain temperature, now called the Néel temperature, the susceptibility falls and the material becomes paramagnetic (weakly magnetic). This behaviour was experimentally confirmed in 1938. Néel also pointed out in 1947 that materials could exist in which the molecular magnets were of unequal strength. This phenomenon is called ferrimagnetism and occurs in lodestone and some ferrites. He also explained the weak magnetism of certain rocks, which made it possible to study the past history of the Earth's magnetic field.

Néel was born in Lyon, France, and gained his doctorate from the Ecole Normale Supérieure, Strasbourg in 1932. He became professor of physics at the University of Strasbourg in 1937. Néel later moved to the University of Grenoble where he was professor of physics until 1976. He became director (1954) and president (1971) of the Grenoble Polytechnic Institute, and director of the Grenoble Institute of Nuclear Studies in 1956.