Non-linear and nanogap devices for large bandwidth, compact terahertz systems

Terahertz (THz) radiation is finding increasing application across a variety of fields including medical diagnostics, art conservation, security screening, industrial quality control, electronics and high-speed wireless communications, due to its non-ionising and non-destructive nature. The challenge is that accessing the THz region requires a combination of photonic and electronic engineering approaches.
The PhD project aims to develop integrated and miniaturised/compact terahertz systems by harnessing the properties of nanostructures. It will pursue this goal through two different approaches. The first is engineering metasurfaces composed of nanostructured non-centrosymmetric crystals to enhance the efficiency of non-linear terahertz generation and detection beyond what is possible with bulk crystals. The second approach involves investigation of nanogaps as photoconductive switches for terahertz generation and detection. These nanogaps, which should enable high electric fields and creative antenna arrangements, are made possible by a novel technique known as adhesion lithography.
The project's methodology will include simulations, design, fabrication and characterisation of metasurfaces and nanogap structures as large bandwidth terahertz emitters and detectors. Ultimately, we envisage that the new emitters and detectors developed will enable miniaturisation and integration of THz systems, increasing the accessibility of terahertz technologies.