Annealing study of EuO films doped with iron and europium

Fe doped and Eu doped EuO films when annealed in vacuum exhibit large changes in the magnetic, electrical, optical, and magneto-optical properties. Annealing for 5 min at 500°C causes the Curie temperature to drop from 150° to 70°K. This effect is related to the insolubility of iron and excess europium in EuO. The annealing temperature for the iron is somewhat higher (500°C) than the annealing temperature for the excess europium (300°C). © 1971 The American Institute of Physics.