Skip to main content

Electron ptychography of 2D materials to deep sub-ångström resolution

Cornell Affiliated Author(s)

Author

Y. Jiang
Z. Chen
Y. Han
P. Deb
H. Gao
S. Xie
P. Purohit
M.W. Tate
J. Park
Sol Gruner
V. Elser
D.A. Muller

Abstract

Aberration-corrected optics have made electron microscopy at atomic resolution a widespread and often essential tool for characterizing nanoscale structures. Image resolution has traditionally been improved by increasing the numerical aperture of the lens (α) and the beam energy, with the state-of-the-art at 300 kiloelectronvolts just entering the deep sub-ångström (that is, less than 0.5 ångström) regime. Two-dimensional (2D) materials are imaged at lower beam energies to avoid displacement damage from large momenta transfers, limiting spatial resolution to about 1 ångström. Here, by combining an electron microscope pixel-array detector with the dynamic range necessary to record the complete distribution of transmitted electrons and full-field ptychography to recover phase information from the full phase space, we increase the spatial resolution well beyond the traditional numerical-aperture-limited resolution. At a beam energy of 80 kiloelectronvolts, our ptychographic reconstruction improves the image contrast of single-atom defects in MoS2 substantially, reaching an information limit close to 5α, which corresponds to an Abbe diffraction-limited resolution of 0.39 ångström, at the electron dose and imaging conditions for which conventional imaging methods reach only 0.98 ångström. © 2018 Macmillan Publishers Ltd., part of Springer Nature.

Date Published

Journal

Nature

Volume

559

Issue

7714

Number of Pages

343-349,

URL

https://www.scopus.com/inward/record.uri?eid=2-s2.0-85050234222&doi=10.1038%2fs41586-018-0298-5&partnerID=40&md5=a0333ed475175fc5cbe6f5f3a8a79ef3

DOI

10.1038/s41586-018-0298-5

Group (Lab)

Sol M. Gruner Group
Veit Elser Group

Funding Source

FA9550-16-1-003
DMR-1429155
DMR 1719875
DMR 1420709
DMR-1539918
DE-SC0005827
DE-SC0017631

Download citation