Negative anisotropic magnetoresistance in 3D metals and alloys containing iridium

A study of anisotropic magnetoresistance (MR) has shown that the addition of Ir to Ni, Co, Fe, Fe.2Ni.8 and Co.3Ni.7 crystalline films causes a negative MR. These negative values occur at room temperature as well as at low temperatures. The MR as defined by ∆ρ - ρ. ρ where the ║ and ⊥ refer to the direction of magnetization relative to the electrical measuring current, can have values ∆ρ ≃.75μ© cm in Co-Ir. At Ir content of 30/0 the ratio Δρ/ρave is -2.60/0. Comparisons are made with other alloy systems, and the implication of negative values of 8. p on theoretical models is considered. © 1984 IEEE