Sub-ångstro¨m structure characterisation: the Brite-Euram route towards one ångstro¨m

Abstract Rather than pushing the point resolution of the electron microscope below 1A˚by increasing the voltage above 1 MeV, we have adopted a different route in which we push down the information limit and retrieve the information by image processing. This goal has now been achieved by using a coherent electron source and optimizing the lens design and the detector configuration and the alignment procedure. The phase is recovered by two different holographic methods: sideband holography and focus variation, whereas for the object structure retrieval, a new method has been developed to “reverse” in a sense the dynamical scattering in the object.

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