Dr. Stephen Hanham / Sub-wavelength Bio-sensing in the Terahertz Domain with Metamaterials

TII Metamaterials and Applications Seminar 2021 - Stephen Hanham - University of Birmingham
The terahertz frequency range (100 GHz to 3 THz) is an emerging area for the electromagnetic spectrum for many chemical, biological and security sensing applications. One area where terahertz sensing is predicted to have a significant impact is in biology, particularly biological liquids. However, the relatively long wavelength of terahertz radiation poses a barrier towards the characterisation of small quantities of biological liquids and new techniques are required to improve the sensitivity and reduce the required sample size. In this talk, I will describe two alternate approaches we have taken recently which exploit the ability of metamaterials to achieve sub-wavelength field confinement and strong field enhancements to improve sensing sensitivity. The first uses spoof surface plasmon polaritons on engineered metal surfaces to provide enhanced THz-matter interaction times and strong interrogating evanescent fields. In the second approach, we demonstrate the integration of terahertz photonic crystal resonators (PCRs) with microfluidics to realise a liquid sensing platform that exploits the PCR’s high quality-factor resonance to enhance the liquid-terahertz interaction. These results represent a step towards a lab-on-a-chip device for the analysis of nano-litre volumes of biological, toxic, explosive, and other liquid types at terahertz frequencies.