Comparing study of magnetic properties of Co–CeO2 thin films with (111) and (100) preferred orientations

Abstract

In recent years, diluted magnetic oxides (DMOs) have been intensively studied aiming for using for spin injection and transportation. In this paper, DMOs of cobalt doped CeO2 (CCO) films with varied cobalt content (0–10%) were fabricated on Al2O3 (0001) substrates by both pulsed laser deposition (PLD) and magnetron sputtering respectively. Pulsed laser deposited and sputtered CCO films showed CeO2 (111) and (100) preferred orientations respectively. These two types of films with different crystallinity had almost the same magnetic and magneto-optical properties, such as room temperature ferromagnetism, non-linearly dependent of the moments on cobalt content, anisotropic magnetisation with an easy axis in out of plane direction and giant Faraday effect. The largest Faraday rotation value of ∼4500° cm−1 at 650 nm wavelength was obtained, for both PLD and magnetron sputtered films. The successful fabrication of ferromagnetic CCO films with controllable preferred orientations on Al2O3 (0001) substrates would be useful to facilitate epitaxial multilayered thin film devices fabrication.