Measuring low alternating magnetic fields by means of Bi-containing rare-earth ferrite-garnet films with planar anisotropy

Abstract

A method of magnetization control through homogeneous rotation has been applied to Bi-containing rare-earth ferrite-garnet films with planar anisotropy. A dynamical range of 160 dB for low alternating magnetic fields detected at f=50 kHz is shown. A minimum detectable field (10−7 Oe) is limited by the sensitivity of polarimeter at the wavelength of the Ar-ion laser λ=514.5 nm, and the output 1 W. The saturation field applied (about 10 Oe) does not result in remanent magnetization in the limits of static orientation vector M resolution. New magneto-optical techniques for investigation with a homogeneous rotation field and for magnetocrystalline anisotropy investigation of in-plane films are described.