Study of dipole interaction in micron-width NiFe/Cu/NiFe/NiO wire using exchange anisotropy

The dipole interaction between a NiFe layer pinned by a NiO and a free NiFe layer in a micron-wide NiFe/Cu/NiFe/NiO wire was studied by changing the d irection of the exchange bias from the NiO layer. The effect of the dipole interaction when the exchange bias was perpendicular to the wire axis was l arger than that when the exchange bias was parallel to the wire axis, and w as consistently explained by the stray field caused by the magnetic charges of the pinned layer. It was demonstrated that this method, using exchange anisotropy, is useful for investigating the dipole interaction between ferr omagnetic materials separated by a nonmagnetic material in small-scale magn etic multilayers. (C) 2001 American Institute of Physics.