Magnetism, structure, and morphology of ultrathin Fe films on Cu3Au(100)

The magnetic, structural, and morphological properties of ultrathin Fe films on Cu3Au(100) have been investigated by low-energy electron diffraction including 1/V measurements, Auger electron spectroscopy, medium-energy electron diffraction, and magneto-optic Kerr effect. The main aim of these studies was to establish the correlation between film structure and magnetism. For this purpose both films deposited at 300 K (RT) and at 150 K (LT) followed by subsequent annealing to 300 K were investigated. Above about monolayer (ML), the films exhibit a perpendicular magnetization, which switches at 3.2+/-0.2 ML for LT and 2.3+/-0.2 kit for RT films in-plant. The reduction of the switching thickness from perpendicular to in-plane with growth temperature is caused by an interdiffusion at the Fe film/substrate interface, At somewhat larger thickness a structural transition is observed. This structural transition is not related to the magnetic reorientation. Contrary to other studies no evidence is found for any fee iran modification. We rather conclude that above 5 ML. the iron film transforms from strained to unstrained bcc(100) Fe.