Magnetotransport Phenomena in [NiFe/Cu] Magnetic Multilayered Nanowires

[Py(20-50 nm)/Cu(5-20 nm)] x n multilayered nanowires were electrodeposited by switching between the deposition potentials of the two constituents [respectively, -1.4 V and -0.3 V for permalloy (NiFe) and Cu deposition]. The magnetotransport properties of single multilayered nanowires have been measured. The MR curve is symmetrically anhysteretic, independent of the thickness of the nonmagnetic Cu layer. The MR ratio can reach values of 2%-2.5%, depending on the thickness of the nonmagnetic Cu layer. The presence of nonmagnetic Cu layers produces a decrease of the axial magnetic anisotropy in the multilayered nanowires, and consequently the magnetic permeability increases at the surface of the nanowires leading to the enhancement of the dc magnetic field effect over the MI response, which can go up to 100%.