Magnetoresistance and Hall Effects for Fe-Ni-M Alloy Thin Films

The relation between the anisotropic magnetoresistivity ratio Δρ/ρ
₀
and the ordinary Hall coefficient R
₀
and extraordinary Hall coefficient R
_s
were studied for Ni-Fe binary alloy and for (Ni
_89.5
Fe
_10.5
)M (M = Co,Cu,Nb,Gd,Al,Si and Bi) ternary alloy thin films, to obtain guidelines in searching for new materials with large values of Δ&#c003C1;/ρ
₀
. The value of Δρ/ρ
₀
increases with increases in the absolute value of R
₀
, and also shows a maximum (Δρ/&3x003C1;
₀
≈ 4%) at R
_s
= 0. For ferromagnetic metals, a large value of Δρ/ρ
₀
can be obtained under the following conditions: (1) the sign of R
₀
is negative and the absolute value of R
₀
is large (carriers are electron-like and the effective carrier density η
_eff
is small), and (2) R
_s
is zero.