We have investigated the room temperature 1/f noise of microstructured soft magnetic Ni80Fe20 films, showing the anisotropic magnetoresistance effect, and of Ni80Fe20/Cu magnetic multilayers, showing the giant magnetoresistance effect. We find that the 1/f noise in magnetic multilayers is considerably enhanced with respect to the noise of the single domain layer, which sets a limit on the usability of giant magnetoresistance materials for low-frequency applications.
Gijs, M. A. M., Giesbers, J. B., Est, van, J. W., Briaire, J., Vandamme, L. K. J., & Beliën, P. (1996). 1/f noise in magnetic Ni80Fe20 single layers and Ni80Fe20/Cu multilayers. Journal of Applied Physics, 80(4), 2539-2541. https://doi.org/10.1063/1.363042