Plasmonic nanostructured metal-oxide-semiconductor reflection modulators.

We propose a plasmonic surface that produces an electrically controlled reflectance as a high-speed intensity modulator. The device is conceived as a metal-oxide-semiconductor capacitor on silicon with its metal structured as a thin patch bearing a contiguous nanoscale grating. The metal structure serves multiple functions as a driving electrode and as a grating coupler for perpendicularly incident p-polarized light to surface plasmons supported by the patch.

Fabrication of a plasmonic modulator incorporating an overlaid grating coupler.

The fabrication of a novel plasmonic reflection modulator is presented and described. The modulator includes plasmon excitation using a diffraction grating coupler and is based on a metal-insulator-semiconductor structure on silicon. Fabrication includes a thin thermal oxide, a plasmonic metal surface defined by optical lithography, a metal grating coupler defined by overlaid e-beam lithography, a passivation layer with metalized vias, and electrical contacts.

Atomically flat symmetric elliptical nanohole arrays in a gold film for ultrasensitive refractive index sensing.

Past works on refractive index sensing using nanohole arrays in metal films typically achieved a resolution of around 10(-4) to 10(-5) refractive index units (RIU), up to 10(-6) with complicated detection setups. This is an order of magnitude worse than commercial Kretschmann-based surface-plasmon resonance (SPR) sensors. Here, we demonstrate intensity-based bulk refractive index sensing in an aqueous environment with a resolution of 9.