The development of terahertz technology for physical, biological, and medical imaging and spectroscopy

The Basic Technology Research Programme provided us with a unique opportunity for the establishment of a technological platform in the UK for imaging and spectroscopy at terahertz (THz) frequencies. This region of the electromagnetic spectrum lies between the microwave and the mid-infrared (300GHz to 30THz), and had remained largely unexplored owing to the lack of suitable sources and detectors. Yet, there was an enormous potential for this spectral range with projected applications ranging from medical and dental imaging and spectroscopy, through to atmospheric sensing, wireless area communications, and astronomy.We have made many key developments on our Basic Technology Research Programme. These include:1) A very broad bandwidth THz spectroscopy system that has been used for studying drugs-of-abuse and explosives;2) A highly sensitive on-chip spectrometer, which can be used for genetic analysis;3) A new design of semiconductor laser operating at more than one frequency simultaneously with applications to gas sensing and pollution monitoring;4) An analysis of pharmaceutical compounds using THz and MRI, and the study of diffusion processes in polymers. This is likely to have impact on controlled-release pharmaceutical mechanisms;5) The construction of a high-pressure combustion chamber, which can be used for making THz measurements of high-pressure flames. This has applications to the optimisation and improvement of aircraft engines.Whilst excellent progress has been made, there is still plenty of research to be undertaken. We thus have applied for a 'Translation' grant to take these research topics further, and determine which of these (several of which we have patented) is likely to be taken up by industry, and find widescale applicability.