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arXiv · 2204.14022

Tip-induced excitonic luminescence nanoscopy of an atomically-resolved van der Waals heterostructure

Luis E. Parra López·Anna Rosławska·Fabrice Scheurer·Stéphane Berciaud·Guillaume Schull
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Abstract

Low-temperature scanning tunneling microscopy is used to probe, with atomic-scale spatial resolution, the intrinsic luminescence of a van der Waals heterostructure, made of a transition metal dichalcogenide monolayer stacked onto a few-layer graphene flake supported by an Au(111) substrate. Sharp emission lines arising from neutral, charged and localised excitons are reported. Their intensities and emission energies vary as a function of the nanoscale environment of the van der Waals heterostructure, explaining the variability of the emission properties observed with diffraction-limited approaches. Our work paves the way towards understanding and control of optoelectronic phenomena in moir\'e superlattices with atomic-scale resolution.

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Luis E. Parra López, Anna Rosławska, Fabrice Scheurer, Stéphane Berciaud, Guillaume Schull. 2022-04-29. Tip-induced excitonic luminescence nanoscopy of an atomically-resolved van der Waals heterostructure. https://doi.org/10.1038/s41563-023-01494-4

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