Title :
Measurements of the anisotropy in permalloy
Author_Institution :
Twente Univ. of Technol., Enschede, Netherlands
fDate :
3/1/1988 12:00:00 AM
Abstract :
A measurement system is described, which accurately determines the anisotropy field Hk and the orientation of the easy-axis in a permalloy film or in any material showing magnetization induced resistance anisotropy. An accuracy of 0.1% in Hk and 0.1 degrees in easy-axis orientation is reached in permalloy when the applied field strength is 2.5 Hk. Deviations from the Stoner-Wohlfarth single domain model can be recognized after the analysis of the measurement. Four electrical contacts have to be positioned on the permalloy in a planar-Hall configuration. Aluminum contacts realized by a standard lithographic process are used, providing a reference for the easy-axis orientation and an accurate relative orientation of the different planar-Hall elements that can be made out of a single film.
Keywords :
Hall effect; Permalloy; magnetic anisotropy; magnetic thin films; Fe-Ni; FeNi-Al; Stoner-Wohlfarth single domain model; anisotropy field; easy-axis; electrical contacts; lithographic process; magnetization induced resistance anisotropy; orientation; permalloy film; planar-Hall configuration; Amplifiers; Anisotropic magnetoresistance; Instruments; Magnetic analysis; Magnetic field measurement; Nonlinear dynamical systems; Position measurement; Q measurement; Signal generators; Voltage;
Journal_Title :
Magnetics, IEEE Transactions on