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arXiv · 1307.6304

Measuring the orbital angular momentum of electron vortex beams using a forked grating

Koh Saitoh·Yuya Hasegawa·Kazuma Hirakawa·Nobuo Tanaka·Masaya Uchida
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Abstract

The present study experimentally examines how an electron vortex beam with orbital angular momentum (OAM) undergoes diffraction through a forked grating. The nth-order diffracted electron vortex beam after passing through a forked grating with a Burgers vector of 1 shows an OAM transfer of nh. Hence, the diffraction patterns become mirror asymmetric owing to the size difference between the electron beams. Such a forked grating, when used in combination with a pinhole located at the diffraction plane, could act as an analyzer to measure the OAM of input electrons.

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Koh Saitoh, Yuya Hasegawa, Kazuma Hirakawa, Nobuo Tanaka, Masaya Uchida. 2013-07-24. Measuring the orbital angular momentum of electron vortex beams using a forked grating. https://doi.org/10.1103/physrevlett.111.074801

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