Electron Holography: Applications to Materials Questions

Impressive progress has been made in the processing and exploration of new material on an atomic scale (nanomaterials). However, the characterization of such materials by the usual transmission electron microscopy (TEM) techniques suffers from the drawback that the phase of the object-modulated electron wave is virtually lost in the recorded intensity images. Electron holography has opened possibilities for analyzing both the amplitude and phase of the electron wave, hence giving access to the object information encoded in the phase. Examples include intrinsic electric and magnetic fields, e.g. in ferroelectrics or ferromagnetics, which substantially determine the object properties and therefore are indispensable for a complete understanding of structure-properties relations.