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arXiv · 2105.09777

Neutral atom scattering based mapping of atomically thin layers

Geetika Bhardwaj·Krishna Rani Sahoo·Rahul Sharma·Parswa Nath·Pranav R. Shirhatti
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Abstract

Imaging surfaces using low energy neutral atom scattering is a relatively recent development in the field of microscopy. In this work we demonstrate that this technique is sensitive enough to distinguish films as thin as a single monolayer from the underlying substrate. Using collimated beams of He and Kr atoms as an incident probe on MoS$_2$ films grown on SiO$_2$/Si substrate, we observe systematic changes in the scattered atom flux which allows us to map the thin MoS$_2$ films. Measurements carried out by varying incidence energy using both He and Kr provides insights into the details of atom-surface collision dynamics and its role in contrast generation.

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Geetika Bhardwaj, Krishna Rani Sahoo, Rahul Sharma, Parswa Nath, Pranav R. Shirhatti. 2021-05-20. Neutral atom scattering based mapping of atomically thin layers. https://doi.org/10.1103/physreva.105.022828

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