Light matter interaction enhancement through spatial confinement in the THz range: towards spectral analysis of single objects

We explored two ways to enhance light matter interaction in the THz range through spatial confinement of the electric field. Firstly, a broadband metallic waveguide with low losses and low dispersion used in a TDS setup to measure samples with volume as low as 200pL. In this proceeding, we explore a resonant structure allowing for tighter confinement at the price of narrower bandwidth. Split ring resonators are resonant structures analogous to LC circuit, where the electric field is confined in the capacitive part of the device. We fabricated SRRs with capacitive gaps as small as 30nm for measurements on extremely low volume sample such as macromolecules or viruses.