GIANT MAGNETORESISTANCE IN FE-BASED BULK MATERIALS

The anisotropy of giant magnetoresistance (GMR) has been observed in m agnetically optimized AlNiCo5 bulk alloys. The magnetic contribution t o the overall resistivity is a function of the direction of the applie d current. GMR amplitudes of 3% at 300 K and 5% at 10 K were measured when the current was applied in the direction of the highest number de nsity of ferromagnetic interfaces. In addition, the influence of the i nitial domain configuration on the GMR amplitude was determined utiliz ing Kerr microscopy. Furthermore the role of domain wall motion has be en evaluated. GMR amplitudes as much as 70% were obtained at 10 K when the sample can freely rotate in the field direction while measuring t he magnetoresistance. (C) 1997 Elsevier Science S.A.