Magnetic anisotropy in TbFe thin films prepared at oblique incidence

Publisher Website
Google Scholar
Abstract
Effects of the incident vapor-beam orientation on magnetic anisotropy of TbFe thin films were investigated. By coevaporation of Tb and Fe on tilted substrates, the angle of incident vapor beam was made to vary from 0° to 60° with respect to each substrate normal. The magnetic measurements were carried out using a vibrating sample magnetometer and a torque magnetometer in applied fields of 15 and 20 kOe, respectively. Assuming an intrinsic anisotropy with a single easy axis, the easy axis orientation and the intrinsic anisotropy energy were estimated. It was found that perpendicular magnetic anisotropy did not deteriorate until the angle of incidence reached 30°. However, the easy axis became tilted from the film normal for angles of incidence larger than 30°; finally, at an incident angle of 60°, it was in the film plane. A rapid increase in the shape anisotropy energy and a simultaneous decrease in the intrinsic anisotropy energy with the angle of incidence are believed to be causes for the loss of perpendicularity in the film.