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arXiv · 2301.13407

A compact and highly collimated atomic/molecular beam source

Geetika Bhardwaj·Saurabh Kumar Singh·Pranav R. Shirhatti
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Abstract

We describe the design, characterization and application of a simple, highly collimated and compact atomic/molecular beam source. This source is based on a segmented capillary design, constructed using a syringe needle. Angular width measurements and free molecular flow simulations show that the segmented structure effectively suppresses atoms travelling in off-axis directions, resulting in a narrow beam of Helium atoms having a width of 7 mrad (full width half maximum). We demonstrate an application of this source by using it for monitoring real-time changes in surface coverage on a clean Cu(110) surface exposed to oxygen, by measuring specular reflectivity of the Helium beam generated using this source.

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Geetika Bhardwaj, Saurabh Kumar Singh, Pranav R. Shirhatti. 2023-01-31. A compact and highly collimated atomic/molecular beam source. https://doi.org/10.1063/5.0145956

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