Magnetic interaction in nanometer line width elliptical ring arrays

Magnetic interactions between permalloy elliptical rings in different arrangements of two-dimensional arrays were investigated. The edge-to-edge distances between units along the long axis were changed from 2μm down to 100nm. Formation of domain walls during magnetization reversals results in magnetostatic coupling between adjacent units. When two neighboring rows were shifted one-half pitch along the short axis to form a shift-type array, large stable field range for vortex states was obtained.