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Title: Achieving sub-0.5-angstrom–resolution ptychography in an uncorrected electron microscope

Subangstrom resolution has long been limited to aberration-corrected electron microscopy, where it is a powerful tool for understanding the atomic structure and properties of matter. Here, we demonstrate electron ptychography in an uncorrected scanning transmission electron microscope (STEM) with deep subangstrom spatial resolution down to 0.44 angstroms, exceeding the conventional resolution of aberration-corrected tools and rivaling their highest ptychographic resolutions​. Our approach, which we demonstrate on twisted two-dimensional materials in a widely available commercial microscope, far surpasses prior ptychographic resolutions (1 to 5 angstroms) of uncorrected STEMs. We further show how geometric aberrations can create optimized, structured beams for dose-efficient electron ptychography. Our results demonstrate that expensive aberration correctors are no longer required for deep subangstrom resolution.

 
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Award ID(s):
1720633 2309037
NSF-PAR ID:
10502492
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
383
Issue:
6685
ISSN:
0036-8075
Page Range / eLocation ID:
865 to 870
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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