Template-stripped plasmonic cup resonators for single-nanohole-based sensing and spectroscopy

Abstract

We have designed and tested a new plasmonic biosensor, featuring a centered nanohole in the base of a recessed metallic nanocup. This configuration enables us to perform independent plasmon-resonance-enhanced single-nanohole transmission spectroscopy on femtoliter volumes of solution. In this thesis we will demonstrate the fabrication, characterization, and application of these novel cup resonator plasmonic biosensors. Utilizing plasmonic confinement to enhance and modulate transmission through a nanohole aperture, the resulting transmission spectra can be used to determine changes in the material properties of a dielectric material located inside the sensing volume of the cup. We have determined, through measurements and simulations, the physical mechanisms causing transmission modulation through the structure. Utilizing this information, we have constructed predictive behavior models for the design and customization of these devices for specific purposes. We show that these structures are responsive to refractive index changes in their surroundings, and propose some possible application of these resonators in biological sensing roles which take advantage of their unique geometry.