Measuring the orbital angular momentum spectrum of an electron beam

Grillo, V. et al. (2017) Measuring the orbital angular momentum spectrum of an electron beam. Nature Communications, 8, 15536. (doi: 10.1038/ncomms15536) (PMID:28537248) (PMCID:PMC5458084)

Abstract

Electron waves that carry orbital angular momentum (OAM) are characterized by a quantized and unbounded magnetic dipole moment parallel to their propagation direction. When interacting with magnetic materials, the wavefunctions of such electrons are inherently modified. Such variations therefore motivate the need to analyse electron wavefunctions, especially their wavefronts, to obtain information regarding the material’s structure. Here, we propose, design and demonstrate the performance of a device based on nanoscale holograms for measuring an electron’s OAM components by spatially separating them. We sort pure and superposed OAM states of electrons with OAM values of between −10 and 10. We employ the device to analyse the OAM spectrum of electrons that have been affected by a micron-scale magnetic dipole, thus establishing that our sorter can be an instrument for nanoscale magnetic spectroscopy.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Lavery, Professor Martin and Padgett, Professor Miles and Boyd, Professor Robert
• Authors: Grillo, V., Tavabi, A. H., Venturi, F., Larocque, H., Balboni, R., Gazzadi, G. C., Frabboni, S., Lu, P.-H., Mafakheri, E., Bouchard, F., Dunin-Borkowski, R. E., Boyd, R. W., Lavery, M. P.J., Padgett, M. J., and Karimi, E.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering; College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Nature Communications
• Publisher: Nature Research
• ISSN: 2041-1723
• ISSN (Online): 2041-1723
• Published Online: 24 May 2017
• Copyright Holders: Copyright © 2017 The Authors
• First Published: First published in Nature Communications 8: 15536
• Publisher Policy: Reproduced under a Creative Commons License