Magnetic information in the light diffracted by a negative dot array of Fe

We have investigated the magnetic properties of an array of holes in an Fe film using the magneto-optic Kerr effect. We develop the theory of diffraction from an array to include magneto-optic effects. The theory allows us to interpret the differences in the magnetic loops observed on the reflected beam and those observed on diffracted spots. The latter contain more detailed information on the magnetic structure in the vicinity of the holes and allow us to infer differences in the switching mechanism for fields applied along the easy and hard axes. © 1999 The American Physical Society.