Localized biomolecular sensing enabled through plasmonic nanocavities
We propose and study an integrated refractive index sensor which is based on a plasmonic slot cavity integrated on silicon-on-insulator wafers. In this device, the guided mode isvertically coupled to the cavity which is a metal-dielectric-metal waveguide and is separated from a photonic wire waveguide by a silicon dioxide spacer. We perform an in-depth study that links the geometrical parameters to the coupling and sensitivity. The strong coupling from the dielectric waveguide to the plasmonic slot waveguide cavity allows a localchange in refractive index to be detectable with a high sensitivity of around 600 nm/RIU in a femto-liter volume. These results are obtained with three-dimensional time domain simulations made with the CST Microwave Studio. The sensing performance of the devices are presented and compared to the practical needs to achieve localized biomolecular sensing
Proc SPIE 9129 2B Osowiecki.pdf
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