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DOE OSTI · 1848073

Imaging atomic-scale chemistry from fused multi-modal electron microscopy

Abstract

Efforts to map atomic-scale chemistry at low doses with minimal noise using electron microscopes are fundamentally limited by inelastic interactions. Here, fused multi-modal electron microscopy offers high signal-to-noise ratio (SNR) recovery of material chemistry at nano- and atomic-resolution by coupling correlated information encoded within both elastic scattering (high-angle annular dark-field (HAADF)) and inelastic spectroscopic signals (electron energy loss (EELS) or energy-dispersive x-ray (EDX)). By linking these simultaneously acquired signals, or modalities, the chemical distribution within nanomaterials can be imaged at significantly lower doses with existing detector hardware. In many cases, the dose requirements can be reduced by over one order of magnitude. This high SNR recovery of chemistry is tested against simulated and experimental atomic resolution data of heterogeneous nanomaterials.

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BibTeXRIS

Schwartz, Jonathan, Di, Zichao Wendy, Jiang, Yi, Fielitz, Alyssa J., Ha, Don-Hyung, Perera, Sanjaya D., El Baggari, Ismail, Robinson, Richard D., Fessler, Jeffrey A., Ophus, Colin, Rozeveld, Steve, Hovden, Robert. 2022-01-27. Imaging atomic-scale chemistry from fused multi-modal electron microscopy. https://doi.org/10.1038/s41524-021-00692-5

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36 MATERIALS SCIENCE↗