Mössbauer Synchrotron and X-ray Studies of Ultrathin YFeO3 Films

Abstract

The YFeO3 orthoferrite is one of the most promising materials for antiferromagnetic (AFM) spintronics. Most studies have dealt with bulk samples, while the thin YFeO3 films possess unusual and variable properties. Ultrathin (3–50 nm) YFeO3 films have been prepared by magnetron sputtering on the r-plane (1 1¯ 0 2)-oriented Al2O3 substrates (r-Al2O3). Their characterization was undertaken by the Mössbauer reflectivity method using a Synchrotron Mössbauer Source and by X-ray diffraction (XRD) including grazing incidence diffraction (GI-XRD). For thin films with different thicknesses, the spin reorientation was detected under the application of the magnetic field of up to 3.5 T. Structural investigations revealed a predominant orthorhombic highly textured YFeO3 phase with (00l) orientation for relatively thick (>10 nm) films. Some inclusions of the Y3Fe5O12 garnet (YIG) phase as well as a small amount of the hexagonal YFeO3 phase were detected in the Mössbauer reflectivity spectra and by XRD.