Lorentz microscopy studies of domain wall trap structures

Initial results on domain wall trap structures fabricated by electron beam lithography are described based on those proposed by micromagnetic simulations. The trap structures are made from thermally evaporated permalloy (Ni/sub 81/Fe/sub 19/) with thickness of 20 nm. Characterisation of the magnetic behaviour of the structures is carried out using the Fresnel mode of Lorentz microscopy as practised in a transmission electron microscope.