Improved Three-Dimensional Reconstructions in Electron Ptychography through Defocus Series Measurements
A detailed analysis of ptychography for three-dimensional (3D) phase reconstructions of thick specimens is performed. 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.
Authors
- Christoph T. Koch (ORCID: https://orcid.org/0000-0002-3984-1523)
- Benedikt Haas (ORCID: https://orcid.org/0000-0002-9301-8511)
- Dana O. Byrne (ORCID: https://orcid.org/0000-0002-4750-181X)
- Scott D. Findlay (ORCID: https://orcid.org/0000-0003-4862-4827)
- Marcel Schloz (ORCID: https://orcid.org/0000-0001-6295-1715)
- Takashi Taniguchi (ORCID: https://orcid.org/0000-0002-1467-3105)
- Kenji Watanabe (ORCID: https://orcid.org/0000-0003-3701-8119)
- Hamish G. Brown (ORCID: https://orcid.org/0000-0003-2292-7766)
- Bryan D. Esser (ORCID: https://orcid.org/0000-0001-8138-447X)
- Jim Ciston (ORCID: https://orcid.org/0000-0002-8774-5747)
- Thomas C. Pekin (ORCID: https://orcid.org/0000-0002-0841-6460)
- Emmanuel Terzoudis-Lumsden
Institutions
- Lawrence Berkeley National Laboratory (US)
- The University of Melbourne (AU)
- National Institute for Materials Science (JP)
- Humboldt-Universität zu Berlin (DE)
- Monash University (AU)
- University of California, Berkeley (US)
Publication Details
- Journal
- Microscopy and Microanalysis
- Published
- 2024-11-18
- DOI
- https://doi.org/10.1093/mam/ozae110
- Citations
- 3
- Primary Topic
- Advanced X-ray Imaging Techniques
- Type
- article
- Field-Weighted Citation Impact
- 1.82