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arXiv · 1810.05838

Proposal for measuring magnetism with patterned apertures

Devendra Negi·Jakob Spiegelberg·Shunsuke Muto·Thomas Thersleff·Masahiro Ohtsuka·Linus Schönström·Kazuyoshi Tatsumi·Jaán Rusz
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Abstract

We propose a magnetic measurement method utilizing a patterned post-sample aperture in a transmission electron microscope. While utilizing electron magnetic circular dichroism, the method circumvents previous needs to shape the electron probe to an electron vortex beam or astigmatic beam. The method can be implemented in standard scanning transmission electron microscopes by replacing the spectrometer entrance aperture with a specially shaped aperture, hereafter called ventilator aperture. The proposed setup is expected to work across the whole range of beam sizes -- from wide parallel beams down to atomic resolution magnetic spectrum imaging.

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Devendra Negi, Jakob Spiegelberg, Shunsuke Muto, Thomas Thersleff, Masahiro Ohtsuka, Linus Schönström, Kazuyoshi Tatsumi, Jaán Rusz. 2018-10-13. Proposal for measuring magnetism with patterned apertures. https://doi.org/10.1103/physrevlett.122.037201

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