UK team targets terahertz imagers

14 Oct 2005

A UK research team will use £2.1 million of funding to develop portable terahertz devices based on InP chips.

From Compound Semiconductor

The UK’s Engineering and Physical Sciences Research Council (EPSRC) has initiated a four-year project to develop portable terahertz devices based on InP semiconductors.

Led by principal investigator Ian Henning from the University of Essex, the £1.2 million ($2.1 million) “PORTRAIT” project also features the Centre for Integrated Photonics (CIP), where the InP components that are crucial to the work will be fabricated.

At CIP, the team will be able to draw on many years of experience in fabricating optoelectronic InP technologies that have been developed for optical communications.

That technology is set to be adapted to produce a new generation of battery-powered “torches” and “cameras” operating in the terahertz region of the spectrum, which sits between the infrared and microwave bands.

The frequency band is useful in applications such as medical imaging, chemical analysis, security and astronomy, largely because many common materials are transparent at terahertz frequencies.

The main drawback is the difficulty associated with producing terahertz radiation. Currently, this is done by aiming high-energy laser pulses at semiconducting materials.

This method has proved sufficient for medical applications, where bulky imaging equipment is expected, and has allowed pioneering companies such as Teraview to commercialize imaging systems. The Cambridge, UK, firm is also involved in the project.

However, to make the technology cheaper, more versatile and to widen the range of applications it is suited to, a much more compact source is needed.

”Making the devices small, low power and portable will allow people to use terahertz radiation in applications like airport security, to look for pollution, and even to be used in a pharmacy or a doctor’s surgery to help with diagnosis,” predicted the team.

The project also involves the University of Bath, the National Physical Laboratory, and University College London.