T-Rays Detect Chemical, Biological Weapons, Find Cancers

ADELAIDE, Australia, December 14, 2004 (ENS) - Forget hiding contraband, explosives or bioweapons. T-rays are here.

New devices that use T-rays, or terahertz rays, to see through clothing and packaging as never before can identify chemical and biological weapons, explosives, or conventional weapons such as guns and knives with pinpoint precision. Even cancers cannot hide from T-rays.

Scientists from America, Europe, Asia and Australia will share the latest advances in T-ray technology at a two day international workshop on TeraHertz for Defence and Security, at Adelaide University.

Opening Thursday, the meeting is sponsored by Australia's Defence Science and Technology Organisation (DSTO).

Terahertz or T-rays are emissions between infra-red and microwaves. T-rays are 1,000 times higher in frequency than microwaves, which are used in cell phones and ovens, and 100 to 1,000 times lower than visible light. Until recently, this had been an unexplored part of the electromagnetic spectrum.

Now scientists are using T-rays to analyze the composition and density of things the rays contact, as well as to image them.

Terahertz light is the range of frequencies between photonics and electronics. (Photo courtesy Jefferson Lab)

"T-rays pass through things like food packaging, clothing, plastic and cardboard enabling us to analyze what's inside. This means they can be used to detect and identify weapons of metal or plastic, illicit drugs or biological hazards like anthrax, even if they were hermetically sealed," Abbott says. "You can find out much more about the substance than you would with optical, infra-red or x-ray imaging, and this helps to identify it precisely."

Because T-rays are low energy, they are also safe to use around people - unlike X-rays, Abbott explains.

"One of the most important recent discoveries is that T-rays can also be used to detect cancer," Abbott says. "Australia is part of the big scientific race to find out why."

Due to their low penetrating power of the human body, T-rays would probably be used to scan the outer skin or, on endoscopes, to scan the bowel and other organs for early signs of cancer, he predicts.

Scientists at the University of Delaware (UD) are working with the Russian Academy of Sciences on a project to develop novel devices that emit terahertz signals for applications in cancer research, biochemical identification, and medical diagnostics.

The research is being conducted at laboratories headed by Dr. James Kolodzey, professor of electrical and computer engineering at UD, and Miron Kagan, director of the Russian Academy’s Institute of Radioengineering and Electronics, with funding provided through the U.S. Civilian Research and Development Foundation (CRDF).

“This CRDF program achieves synergy by combining the scientific strengths of the groups in St. Petersburg and Moscow in Russia with the experimental abilities of the University of Delaware,” Kolodzey said.

The UD research team is recognized as an international leader in the development of terahertz nanotechnology, last year announcing it had discovered a means to harness the power of the terahertz frequencies in a palm sized device using a semiconductor nanostructure.

Research is preliminary, but Kolodzey says the palm device might one day detect cancers in the body, determine from a distance the chemicals in a hazardous waste spill, or find victims trapped under rubble.

The new imaging technology came to life in September 2002 when the European Space Agency’s (ESA) StarTiger team captured the world's first terahertz picture of a human hand.

"When we started last June we set an ambitious goal: to build in four months the first compact submillimetre wave imager with near real time image capturing using state of the art micro-machining technology," said Peter de Maagt, ESA’s StarTiger project manager, "we reached this goal when the first terahertz images were taken in September."

The StarTiger color terahertz imager is here seen under test in The Netherlands. It is imaging the hand of Peter de Maagt, the European Space Agency’s StarTiger project manager. (Photo courtesy ESA)

Unlike radio waves, which travel through objects, terazhertz frequencies are partially absorbed by objects or by the human body. But terahertz frequencies are not harmful to humans the way X-rays are because they vibrate at lower energy levels.

Abbott says that the potential applications of T-rays are huge, from food safety and quality monitoring, to disease detection, airport security, postal scans for drugs, explosives or bioweapons, military threat detection and medical diagnosis.

T-rays can also penetrate poor weather, dust and smoke far better than infrared or visible systems, says UK researcher Dr. Roger Appleby. "Imaging in this band offers the opportunity to navigate and perform surveillance in poor visibility."

T-rays will also provide forensic analysts with new tools in the fight against crime, says Dr. Robert Miles of the University of Leeds. The ability of terahertz radiation to pass through different substances and differentiate between them on the basis of their composition will lead to much more precise identification of different types of glass, fabrics, lubricating oils and paper.

The father of T-rays, Professor Xi-Cheng Zhang of Rensselaer Polytechnic Institute in New York, says T-rays offer the opportunity for transformational advances in defense and security.

"Recent work shows that T-rays have promise as a means of identifying explosive compounds, Zhang said. "Unique features in THz frequency have been obtained. Examples of such applications to identify terrorist threats include terahertz spectroscopy of biomaterial identification with fingerprint in terahertz range, and remote sensing and imaging of explosive targets."

Zhang says that T-rays also offer promise for the emerging science of nanotechnology.

Workshop organizer Derek Abbott is associate professor at the University of Adelaide and director of its Center for Biomedical Engineering. (Photo courtesy U. Adelaide)

"This means we will soon be able to use T-rays to study human cells at below the cellular level."

At the Adelaide workshop, the focus will be on warfare applications. U.S. Army scientist Dr. James O. Jensen will give a presentation on U.S. Army research in terahertz sensing science and electronic technology for effective battlefield deployment.

Dr. Sandra Biedron from the U.S. Energy Department's Argonne National Laboratory, will discuss the use of T-rays for homeland security with a focus on compact electron beam based sources.

Dr. Anthony Thomas of the Jefferson Lab in the United States will discuss power and portability issues associated with the use of high power T-ray generation for concealed weapon detection and battlefield communications. Jefferson Lab is managed and operated by Southeastern Universities Research Association for the U.S. Department of Energy.