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arXiv · 1805.02120

Molecular Sensing with Tunable Graphene Plasmons

Andrea Marini·Iván Silveiro·F. Javier García de Abajo
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Abstract

We study the potential of graphene plasmons for spectrometer-free sensing based on surface-enhanced infrared absorption and Raman scattering. The large electrical tunability of these excitations enables an accurate identification of infrared molecular resonances by recording broadband absorption or inelastic scattering, replacing wavelength-resolved light collection by a signal integrated over photon energy as a function of the graphene doping level. The high quality factor of graphene plasmons plays a central role in the proposed detection techniques, which we show to be capable of providing label-free identification of the molecular vibration fingerprints. We find an enhancement of the absorption and inelastic scattering cross-sections by 3-4 orders of magnitude for molecules in close proximity to doped graphene nanodisks under currently feasible conditions. Our results pave the way for the development of novel cost-effective sensors capable of identifying spectral signatures of molecules without using spectrometers and laser sources.

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Andrea Marini, Iván Silveiro, F. Javier García de Abajo. 2018-05-05. Molecular Sensing with Tunable Graphene Plasmons. https://doi.org/10.1021/acsphotonics.5b00067

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