Transmission electron microscopies of magnetic microstructures

Since its introduction 40 years ago Lorentz microscopy has been used extensively to study domain structures in magnetic thin films and elements. Here we review the principal imaging modes, with emphasis on those introduced most recently, and discuss their advantages and drawbacks. Special emphasis is given to the development of methodologies which allow the magnetic state of a specimen to be changed in situ and which allow a full quantitative description of the spatial variation of magnetic induction to be extracted. Examples of each are presented. Finally, we discuss areas where further technique development will be beneficial.