The origin of hydrocarbon contamination on graphene and other van der Waals materials

Our group has identified, using low temperature STM and infrared spectroscopy measurements, the structure and composition of the hydrocarbon contamination found on many van der Waals material surfaces (hBN, MoS2, etc.). When exposing fresh surfaces to ambient conditions, the initial contamination layer is replaced within days by a monolayer of straight chain alkanes. These alkanes […]

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Crumpled graphene

Visible plasmons in ultra-corrugated graphene

In our recent paper published in Nature Nanotechnology, we show that the plasmon frequencies of graphene can be tuned from terahertz frequencies into the visible range. This enables extremely sensitive detection of molecules from femtomolar concentrations by Raman spectroscopy.

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