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arXiv · 2410.06871

Semicircular-aperture illumination scanning transmission electron microscopy

Akira Yasuhara·Fumio Hosokawa·Sadayuki Asaoka·Teppei Akiyama·Tomokazu Iyoda·Chikako Nakayama·Takumi Sannomiya
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Abstract

Scanning transmission electron microscopy (STEM) provides high-resolution visualization of atomic structures as well as various functional imaging modes utilizing phase contrast. In this study we introduce a semicircular aperture in STEM bright field imaging, which gives a phase contrast transfer function that becomes complex and includes both lower and higher spatial frequency contrast transfer. This approach offers significant advantages over conventional phase plate methods, having no charge accumulation, degradation, or unwanted background noise, which are all problematic in the phase plate material. Also compared to the differential phase contrast or ptychography equipment, this semicircular aperture is far less costly. We apply this approach to visualization of polymer, biological and magnetic samples.

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Akira Yasuhara, Fumio Hosokawa, Sadayuki Asaoka, Teppei Akiyama, Tomokazu Iyoda, Chikako Nakayama, Takumi Sannomiya. 2024-10-09. Semicircular-aperture illumination scanning transmission electron microscopy. https://doi.org/10.1016/j.ultramic.2025.114103

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