Micron-scale magnetic structures for atom optics

Abstract

Magnetic structures with periodicities on the scale of a micron have been constructed by magneto-optical recording on perpendicularly magnetised TbFeCo film with a focussed diode laser beam in the presence of an external field, and by microfabricating perpendicularly magnetised grooved CoCr structures. Strong reflection signals and predominantly specular reflection have been realised for beams of laser-cooled caesium atoms normally incident on both types of structure. Preliminary measurements of the specularity for a grooved $\text{a=1}$ μm magnetic structure are particularly encouraging.