Cheaper tera

Physicists at the University of Strathclyde have found a new way to produce terahertz pulses - a safe form of radiation that could be used in medical imaging, biological research and homeland security.

The method developed by Dr Klaas Wynne and Gregor H. Welsh, can be used to cultivate a range of imaging technologies, from new machines to detect cancerous cells, to security systems to reveal weapons and explosives concealed under clothing.

'Terahertz radiation is emitted from all objects at room temperature, and in its pulsed form has been studied intensely by scientists over the last 10 years because of its potential applications in medicine, homeland security, and laboratory research,' Dr Wynne said.

The scientists found they could generate terahertz pulses by firing an ultra-fast laser at a small, nano-engineered piece of grooved glass topped with gold.

'It's a relatively cheap way of creating the radiation that we believe could be adapted for large-scale industry use,' Dr Wynne added.

'Our method of producing terahertz is a bit like a modern, ultra-fast version of Henrich Hertz' 1886 experiment with which he discovered radio waves, but scaled down in size and duration by a billion times.'

A paper describing the method has been published in Physical Review Letters journal.