Superposition of Fraunhofer Diffractions from Fork-Shaped Gratings and their Openings with Electron Vortex Beam
نویسندگان
چکیده
We fabricated a fork-shaped grating [1] made from a SiN-membrane with a 200-nm-thickness by using a focused ion beam machine (FB-2100, Hitachi High-Technologies Corp.). The maximum grating size in one direction was 10 μm. Electron diffractions from the gratings were observed with a 300-kV field emission electron microscope (H-9000) [2]. The optical system was constructed for small angle diffraction with a camera length of 150 m and was similar to a twin-Foucault imaging system [3].
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