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DOE OSTI · 2507172

Improved Three-Dimensional Reconstructions in Electron Ptychography through Defocus Series Measurements

Schloz, Marcel·Pekin, Thomas C.·Brown, Hamish G.·Byrne, Dana O.·Esser, Bryan D.·Terzoudis-Lumsden, Emmanuel·Taniguchi, Takashi·Watanabe, Kenji·Findlay, Scott D.·Haas, Benedikt·Ciston, Jim·Koch, Christoph T.
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Abstract

A detailed analysis of ptychography for three-dimensional (3D) phase reconstructions of thick specimens is performed. Here, we introduce multi-focus ptychography, which incorporates a 4D-STEM defocus series to enhance the quality of 3D reconstructions along the beam direction through a higher overdetermination ratio. This method is compared with established multi-slice ptychography techniques, such as conventional ptychography, regularized ptychography, and multi-mode ptychography. Additionally, we contrast multi-focus ptychography with an alternative method that uses virtual optical sectioning through a reconstructed scattering matrix (S-matrix), which offers more precise 3D structure information compared to conventional ptychography. Our findings from multiple 3D reconstructions based on simulated and experimental data demonstrate that multi-focus ptychography surpasses other techniques, particularly in accurately reconstructing the surfaces and interface regions of thick specimens.

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3D reconstruction4D-STEM75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITYdepth sectioningptychography

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BibTeXRIS

Schloz, Marcel, Pekin, Thomas C., Brown, Hamish G., Byrne, Dana O., Esser, Bryan D., Terzoudis-Lumsden, Emmanuel, Taniguchi, Takashi, Watanabe, Kenji, Findlay, Scott D., Haas, Benedikt, Ciston, Jim, Koch, Christoph T.. 2024-11-18. Improved Three-Dimensional Reconstructions in Electron Ptychography through Defocus Series Measurements. https://doi.org/10.1093/mam%2Fozae110

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