Vortex beams for atomic resolution dichroism.

Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA.
Journal of electron microscopy (Impact Factor: 1.31). 09/2011; 60(5):295-300. DOI: 10.1093/jmicro/dfr069
Source: PubMed

ABSTRACT Vortex beams carrying orbital angular momentum have been produced recently with electron microscopy by interfering an incident electron beam with a grid containing dislocations. Here, we present an analytical derivation of vortex wave functions in reciprocal and real space. We outline their mathematical and physical properties and describe the conditions under which vortex beams can be used in scanning transmission microscopy to measure magnetic properties of materials at the atomic scale.

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