In these models, ferromagnetism is described as a cooperative phenomenon based on the interaction between the magnetic moments.
Most of his research, however, was on magnetism, where, starting in 1938, he developed the collective electron theory of ferromagnetism.
Without quantum mechanics, there would be no diamagnetism, paramagnetism or ferromagnetism.
He carried out research in the areas of kinetic theory of gases, electrical conductivity, gas discharges, heat radiation, ferromagnetism and photochemistry.
Like ferromagnetism and atomic spectral lines, superconductivity is a quantum mechanical phenomenon.
The strongest effect is on permanent magnets, which have persistent magnetic moments caused by ferromagnetism.
Early investigations studied the coexistence of conventional "s" -wave superconductivity with itinerant ferromagnetism.
Other low-temperature ground states that occur in such materials are superconductivity, ferromagnetism and antiferromagnetism.
