Molecular Sensing with Tunable Graphene Plasmons
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.
Cite
@article{arxiv.1805.02120,
title = {Molecular Sensing with Tunable Graphene Plasmons},
author = {Andrea Marini and Iván Silveiro and F. Javier García de Abajo},
journal= {arXiv preprint arXiv:1805.02120},
year = {2018}
}