Extension of focal depth by electron quasi-Bessel beam in atomic-resolution scanning transmission electron microscopy. (1st November 2022)

• Record Type: Journal Article
• Authors: Ishida, Takafumi; Owaki, Takeshi; Ohtsuka, Masahiro; Kuwahara, Makoto; Saitoh, Koh; Kawasaki, Tadahiro
• Is Part Of: Applied physics express. Volume 15:Number 11(2022)
• Publication Date: 2022-11-01
• Subjects: electron Bessel beam -- scanning transmission electron microscopy -- annular aperture; Physics -- Periodicals; Technology -- Periodicals; 621.05
• DOI: 10.35848/1882-0786/ac96ce
• Languages: English
• ISSNs: 1882-0778

Abstract

Abstract: Extension of the focal depth of a sub-nanometer-sized electron probe in a scanning transmission electron microscope was demonstrated using an electron Bessel beam. We observed atomically-resolved annular dark-field scanning transmission electron microscope images of SrTiO3 in the [001] direction with defocus using an electron quasi-Bessel beam generated by a ring-shaped aperture in an aberration-corrected probe-forming system. The experimental results show that the defocus range over which images with a 0.2 nm spatial resolution can be acquired using the electron quasi-Bessel beam is three times longer than the corresponding defocus range for a conventional beam.