title: Large variation of magnetic properties of amorphous Fe-Zr thin films with Ar pressure during sputtering.
abstract: A large change is observed in the magnetic properties of amorphous Fe-Zr thin films sputtered at different Ar pressures. The change depends on the composition of the alloys and at compositions near 60 at.% Fe, for example, the magnetisation measured at 10 kOe increases 30-fold with an increase in the Ar pressure from 2 to 10 mTorr. The magnetic properties are well explained by a combination of two phenomena-superparamagnetism and spin glass behaviours-and the large change is partly related to the number density of a magnetically correlated region. Examinations of the microstructure by X-ray diffraction, transmission electron microscopy, and X-ray absorption fine structure spectroscopy reveal no appreciable difference in it as a function of the Ar pressure. This indicates that even a very slight change in the microstructure can greatly affect the magnetic properties of amorphous Fe-Zr thin films, thereby opening up the possibility of employing the magnetic properties of amorphous alloys for the characterisation of amorphous microstructures.
authors.affiliation: Department of Nano Semiconductor Engineering, Korea University, Seoul 02841, Korea.
authors.forename: Miri
authors.initials: M
authors.lastname: Kim
authors.affiliation: Energy and Environmental Research Team, Beamline Division, Pohang Accelerator Laboratory, Pohang 37673, Korea.
authors.forename: Nark-Eon
authors.initials: NE
authors.lastname: Sung
authors.affiliation: Department of Nano Semiconductor Engineering, Korea University, Seoul 02841, Korea.|Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.
authors.forename: Sang Ho
authors.initials: SH
authors.lastname: Lim