Engineering terahertz photonic devices using semiconductor nanowires

Key Objectives/Aim of the research:

Mixed halide perovskites are highly promising semiconductors for photovoltaic applications due to their high optical absorption, long charge carrier lifetimes, versatile low-cost processing techniques etc. Their performance has improved dramatically over the past decade, increasing in power conversion efficiency and gradually overcoming the problems of temperature- and humidity-induced instability.

Semiconductor nanowires can be engineered to achieve short charge-carrier lifetimes and high carrier mobilities, which enable them to be switched electronically or optically at high terahertz (THz) frequencies. Their crystal structure, facets, shape and orientation can be controlled to achieve tailored electrooptic coefficients and polarizability. These advantages set nanowires apart from traditional planar semiconductors.

This project aims to investigate and understand the underlying optoelectronic mechanisms of photoinduced charge carriers transport within semiconductor materials such as mixed halide perovskite and semiconductor nanowires and how tuning fabrication factors improves their electrical and optical properties.

Novel Physical Sciences/Engineering Methodology:

The project will employ optical pump terahertz probe spectroscopy to investigate and characterise the ultrafast electrical and optical properties of semiconductor nanowires and mixed halide perovskites with high accuracy which would guide the development of terahertz devices and perovskite solar cells.