Multilayer thin films for use as fluxgates cores

Abstract

Ways to increase the sensitivity of differential fluxgates based on use of film cores with a certain domain structure are considered. The results of magnetic investigations of multilayer thin permalloy films with uniaxial anisotropy, used as cores of fluxgates, are presented. The performed analysis of fluxgate operation makes possible to calculate its sensitivity from main magnetization curve or hysteresis loop. The magnetization-field dependence for a uniaxial ferromagnet with dispersion of easy magnetization axis was found. It is shown that to increase the signal-to-noise ratio, it is necessary to fabricate film layers in which the magnetization reversal by excitation fields occurs due to reversible rotation of magnetization.