Contrast inversion in neutral atom microscopy using atomic cluster beams

TL;DR

This paper investigates the use of atomic cluster beams in neutral atom microscopy, demonstrating contrast inversion phenomena and exploring their implications for high-resolution imaging.

Contribution

It introduces the use of Kr atomic cluster beams in NAM, revealing contrast inversion effects and expanding the understanding of cluster-surface interactions.

Findings

Contrast inversion observed in NAM images with Kr clusters

Topographical contrast achievable with atomic clusters

Implications for high-resolution neutral atom microscopy

Abstract

This work explores the possibility of atomic cluster beams as a probe for neutral atom microscopy (NAM) measurements. Using a beam of Kr clusters with mean size $\sim$ 10$^4$ atoms/cluster we demonstrate that topographical contrast can be obtained, similar to that in the case of monoatomic beams. Further, using atomically thin films of MoS$_2$ grown on SiO$_2$/Si substrate we show that NAM imaging using Kr clusters is also possible in domains where topographical contrast is not expected. Surprisingly, these images show an inverted contrast pattern when compared to the case of monoatomic beams. We attempt to understand these observations on the basis of angular distributions resulting from cluster-surface scattering. Finally, we discuss the implications of these results towards achieving a high lateral resolution neutral atom microscope using atomic cluster beams.