Terahertz characterisation of nanomaterials for device applications

Semiconductor nanomaterials have emerged as promising candidates for novel optoelectronic and spintronic devices. To harness these advantageous properties, an in-depth understanding of their ultrafast carrier dynamics is essential. The terahertz frequency range provides the perfect probe for investigating key optoelectronic processes, as its energy range encompasses low-energy excitations, such as plasmons and phonons. Terahertz spectroscopy is therefore a unique non-contact tool for examining the electrical conductivity of a material. This project will utilise optical-pump terahertz-probe spectroscopy to examine the photoinduced conductivity response of these exciting materials, directly extracting key transport parameters, such as carrier mobility and lifetimes. It will conduct investigation into the ultrafast carrier dynamics of semiconductor nanowires. This project will use terahertz spectroscopy and near-field microscopy to examine their optoelectronic properties for application in terahertz devices, such as single-nanowire terahertz photodetectors and terahertz modulators.