Nanostructured Ferromagnetic-Wire/Insulator Composites

A research and development effort now in progress is focused on nano-structured ferromagnetic- wire/insulator composite materials to be used as the magnetic-core materials of sensors for measuring weak magnetic fields. Figure 1 schematically depicts an example of such a sensor — a flux-gate magnetometer that resembles a traditional orthogonal flux-gate magnetometer except that, instead of a single cylindrical ferromagnetic core, there are multiple parallel ferromagnetic wire cores packed together with insulating material between them. An overriding consideration in the design, fabrication, and operation of such a magnetometer is that high effective magnetic permeability of the core is necessary as one of the prerequisites for obtaining high sensitivity.