Magnetic phase transitions in nanocrystalline erbium

Nanocrystalline samples of 99.9% pure erbium with particle sizes between 10 and 70 nm have been produced by the inert gas condensation technique. Magnetic susceptibility measurements on samples compacted to between 50% and 75% of bulk density indicate a modification in the high-temperature phases and superparamagnetic behavior at low temperatures. ESR signals near g=10 are probably due to Er compounds which may form during the production process.