Ferromagnetic resonance

Ferromagnetic resonance, or FMR, is a spectroscopic technique to probe the UHF radiation by ferromagnetic materials in 1911. A qualitative explanation of FMR along with an explanation of the results from Arkad'yev was offered up by Ya. G. Dorfman in 1923 when he suggested that the optical transitions due to Zeeman splitting could provide a way to study ferromagnetic structure. FMR is very similar to atomic nuclei.