In a transmission electron microscope, electrons are described by matter-waves with wavelengths five orders of magnitude smaller than optical electromagnetic waves. Analogous to optical holography, electron wavefronts can be shaped using nanoscale holographic gratings. Here we demonstrate a novel, scalable nanofabrication method for creating off-axis holographic gratings that demonstrate near ideal diffraction efficiencies for binary, sinusoidal, and blazed grating groove profiles. We show that this method can produce up to 50 µm diameter area gratings that diffract up to 68% of the transmitted electron wave into a desired diffraction order with less than 7% into any other order. Additionally, we find that the amount of inelastically scattered electrons from the material gratings remaining in the coherent diffraction orders from the gratings is negligible in the far field.
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http://dx.doi.org/10.1364/AO.376876 | DOI Listing |
Rev Sci Instrum
December 2024
Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
An objective soft x-ray flat-field spectrograph employing a laminar-type bilayer coated, varied-line-spacing, spherical grating was designed to improve the detection limit and sensitivity of soft x-ray flat-field spectrographs in a region of 250-550 eV. As a design criterion, spectral flux, SF, [Hatano et al., Appl.
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