2021/08/10 by Christoph K. Hofer, Kimmo Mustonen, Hofer, Christoph +5
Biochemistry, Genetics and Molecular Biology · Engineering · #Advanced Electron Microscopy Techniques and Applications #Advanced Semiconductor Detectors and Materials #Applied Physics (physics.app-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Photocathodes and Microchannel Plates
paper · pdf · doi:10.48550/arxiv.2108.04625
openalex publication_date 2021/08/10 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
From ripples to defects, edges and grain boundaries, the 3D atomic structure of 2D materials is critical to their properties. However the damage inflicted by conventional 3D analysis precludes its use with fragile 2D materials, particularly for the analysis of local defects. Here we dramatically increase the potential for precise local 3D atomic structure analysis of 2D materials, with both greatly improved dose efficiency and sensitivity to light elements. We demonstrate light atoms can now be located in complex 2D materials with picometer precision at doses 30 times lower than previously possible. Moreover we demonstrate this using a material, WS2, in which the light S atoms are in fact practically invisible to conventional methods. The key advance is combining the concept of few tilt tomography with highly dose efficient ptychography in scanning transmission electron microscopy. We further demonstrate the method experimentally with the even more challenging and newly discovered 2D CuI, leveraging a new extremely high temporal resolution camera.