Anisotropic Magnetoresistance and Hall Effects for Ni-Co Alloy Thin Films

The relationship between anisotropic magnetoresistance and the Hall effect was studied for fcc Ni-Co binary alloy thin films. The maximum value of ¿¿/¿0 was 5.3%, obtained for 75 at % Ni-Co alloy. At this alloy composition, the ordinary Hall coefficient R0 was ¿2.0×l0^~12 V- cm/A-Oe, and the extraordinary Hall coefficient R3 was 0.6×10^¿10 V-cm/A-G, or very nearly zero. It was also found that the magnetic moment per atom was 0.9¿BLB at this same alloy composition. All these relationships were found to be nearly the same as for Ni-Fe alloys. These results suggest that a large value of ¿¿/¿0 can be obtained in fcc Ni-base alloys under the following conditions: (1) when R0 is negative-valued and its absolute value is large, (2) when Rs is close to zero, and (3) when the magnetic moment per atom is 0.9¿B.