Guidelines for the evaluation of magnetotransport parameters from measurements on thin strip-shaped samples of bulk metallic ferromagnets with finite residual resistivity
Wigner Research Centre for Physics, Hungarian Academy of Sciences, Konkoly-Thege út 29-33, H-1121, Budapest, Hungary
* e-mail: email@example.com
Accepted: 29 October 2018
Published online: 18 December 2018
In the present paper, the formulae are summarized for the evaluation of magnetoresistance data from the measured field dependence of the resistivity obtained on thin strip-shaped samples of ferromagnetic metals and alloys with a finite residual resistivity for various relative orientations of the magnetic field and the measuring current. This sample shape simplifies the problem in that the specimen shape can be approximated with a general ellipsoid for which the demagnetizing fields can be estimated with sufficient accuracy from tabulated data. First, the various experimental configurations are defined for the magnetotransport measurements. Then, the formulae for describing the field-dependence of the resistivity in metallic ferromagnets with finite residual resistivity are discussed, by treating separately the case of low and high temperatures, low and high being defined with respect to the Curie temperature of the ferromagnet under study. The extraction of some magnetotransport parameters (anisotropic magnetoresistance and Hall effect) often requires an extrapolation of the measured data to zero magnetic field or zero magnetic induction and this will also be discussed. Finally, a summary of the relations between the experimentally measured magnetotransport parameters and those derived from theoretical calculations will be given.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature, 2018