Magneto-optic vector magnetometry of CoFeCrSiB amorphous ribbons

Abstract

A magneto-optic method suitable for investigation of soft magnetic ribbons is proposed that combines the internal magnetic field induced by a current flowing through the ribbon axis with the external magnetic field generated by an air coil. The method eliminates effects of demagnetizing factor and shape anisotropy on measured hysteresis loops. Both in-plane magnetization components are measured by means of magneto-optic vector magnetometry. The method is applied to study magnetic properties of CoFeCrSiB amorphous ribbons showing asymmetric giant magnetoimpedance effects. A coherent rotation of magnetization and in-plane easy axis inclined from the ribbon axis is observed. It corresponds to helical magnetic anisotropy originating from the preparation processes.