Effect of magnetic field on the electrical properties:

As compared to bulk values, MR values turn out to be quite large in thin film samples depending upon the multilayer nature and magnetic properties.

Baibich et al. [1] first experimentally demonstrated giant MR (GMR) in Fe/Cr/Fe multilayer structure as displayed in Figure 27.02. They found that the field required for obtaining large GMR effect is large (~ 20 kOe).

Figure 27.02: Schematic view of multilayer films and MR as a function of applied magnetic field.

Ref.[1]. Baibich et al., Phys. Rev. Lett. 61 (1988) 2472.