Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

'T-ray' breakthrough signals next generation of security sensors

06.02.2008
A new generation of sensors for detecting explosives and poisons could be developed following new research into a type of radiation known as T-rays, published today (3 February) in Nature Photonics.

The research shows that these T-rays, electromagnetic waves in the far infrared part of the electromagnetic spectrum that have a wavelength 500 times longer than visible light, can be guided along the surface of a specially designed material, known as a metamaterial. Being able to control T-rays in this way is essential if this type of radiation is to be used in many real world applications.

Researchers believe one of the areas with the most potential to use T-rays is security sensing and scanning, because many of the molecules in explosives and biological agents like anthrax strongly absorb this radiation. If T-rays are tightly confined on surfaces in contact with such molecules then the detection sensitivity is greatly increased.

Simple metallic surfaces have been used to control T-ray propagation before, but these only weakly guide the radiation, which extends as a weak field many centimetres above the surface of the material, thus rendering it less effective for sensing. The new study has now shown that a metamaterial surface draws T-rays close to it, creating a very strong field less than a millimetre above the surface. This greatly enhances the absorption by molecules on the surface making highly effective sensing techniques possible.

The study was performed by a team of UK and Spanish physicists led in the UK by Dr Stefan Maier from Imperial College London's Department of Physics, and Dr Steve Andrews of the University of Bath. Dr Maier explains why their metamaterial design is so important:

"T-rays have the potential to revolutionise security screening for dangerous materials such as explosives. Until now it hasn't been possible to exert the necessary control and guidance over pulses of this kind of radiation for it to have been usable in real world applications. We have shown with our material that it is possible to tightly guide T-rays along a metal sheet, possibly even around corners, increasing their suitability for a wide range of situations."

A metamaterial is a man-made material with designed electromagnetic properties which are impossible for natural materials to possess. The metamaterial created for this new research consists of a metallic surface textured with a two-dimensional array of pits. The researchers chose the dimensions of the pits so that T-rays are drawn closely to them as they travel along the surface.

Dr Andrews says that although the results of their study are very promising, more work is needed to refine the technology before such surfaces can be used for sensing applications. "At the moment only a small number of the frequencies that make up a pulse of T-ray radiation are closely confined by our metamaterial. More sophisticated designs are needed in order to make sure that the whole pulse is affected by the surface structure, so that absorption features of molecules can be clearly identified."

Dr Maier and Dr Andrews designed the metamaterial together with colleagues from Universities in Madrid and Zaragoza, with financial support from the US Air Force and the Royal Society. Their breakthrough is based on previous theoretical predictions obtained by the Spanish team together with Imperial's Professor John Pendry, published in Science in 2004.

danielle reeves | alfa
Further information:
http://www.imperial.ac.uk
http://www.bath.ac.uk/news/releases/

More articles from Physics and Astronomy:

nachricht New NASA study improves search for habitable worlds
20.10.2017 | NASA/Goddard Space Flight Center

nachricht Physics boosts artificial intelligence methods
19.10.2017 | California Institute of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Terahertz spectroscopy goes nano

20.10.2017 | Information Technology

Strange but true: Turning a material upside down can sometimes make it softer

20.10.2017 | Materials Sciences

NRL clarifies valley polarization for electronic and optoelectronic technologies

20.10.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>