||UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS
Conference: Bucharest University Faculty of Physics 2019 Meeting
Section: Solid State Physics and Materials Science
Interplay of magneto-strictive and magneto-transport properties of Fe-Dy ribbons
Claudiu LOCOVEI (1,2), Anda Elena STANCIU (1), Gabriel SCHINTEIE (1), Nicusor IACOB (1), Aurel LECA (1), Mihaela SOFRONIE (1), Victor KUNCSER (1)
1) National Institute for Materials Physics, P.O.Box MG-7, 077125, Bucharest-Magurele, Romania
2) Bucharest University, Faculty of Physics, 077125, Bucharest-Magurele, Romania
non-collinear spin structure, magnetic anisotropy, unusual magneto-transport
features, rare earth – transition metals alloys
Magnetic interactions and their influence on the magneto-transport and magneto-
strictive properties of Fe-Dy amorphous systems with non-collinear magnetic structure were
investigated. Interesting magneto-functionalities of such Fe-Dy alloys of interest for
applications in spintronics and magneto-optical recording are envisaged.
Fe-Dy ribbons of different compositions were prepared by induction melting of the
elements followed by ultra-fast quenching on a drum armature. The formation of the
amorphous phase was probed via X-Ray Diffraction (XRD) and Mossbauer spectroscopy.
The specific spin structure of such sperimagnetic systems was completely resolved (over both
Fe and Dy magnetic sublattices) by corroborating in field Transmission Mossbauer
Spectroscopy (TMS) and magnetometry data. Considering that the observed spins
reorientation under temperature variation is equivalent to a reorientation of the magnetic
moments under a tensile stress, a reach information on magneto-strictive effects was inferred
from TMS data providing the average angle between the mean direction of the hyperfine
magnetic field and the ribbon plane, as collected at different temperatures. Both positive and
negative magneto-striction coefficients were evidenced, depending on the Dy content and
temperature. Moreover, the observed atypical magneto-resistance curves were interpreted as
due to the electron scattering mechanism on the non-collinear spin structure and to an
additional contribution related to size variations by reorientation of the magnetic moments
under an applied magnetic field specific to such magneto-strictive materials.
This work was supported by the Romanian Ministry of Research via the Core Program PN21N, PN-III-P1-1.2-PCCDI-2017-0871 and POC P_37_697 REBMAT (contract 28/01.09.2016).