Featured Research

from universities, journals, and other organizations

'T-ray' Breakthrough Signals Next Generation Of Security Sensors

Date:
February 11, 2008
Source:
Imperial College London
Summary:
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. 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.

Artist's impression of researchers' specially designed metamaterial, with an array of pits which guides T-rays.
Credit: Image courtesy of Imperial College London

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.

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.

Authors: C. R. Williams, S. R. Andrews, S. A. Maier, A. I. Fernandez-Dominguez, L. Martin-Moreno, and F. J. Garcia-Vidal.

Journal article: 'Highly confined guiding of terahertz surface plasmon-polaritons on structured metal surfaces' Nature Photonics, February 3, 2008.


Story Source:

The above story is based on materials provided by Imperial College London. Note: Materials may be edited for content and length.


Cite This Page:

Imperial College London. "'T-ray' Breakthrough Signals Next Generation Of Security Sensors." ScienceDaily. ScienceDaily, 11 February 2008. <www.sciencedaily.com/releases/2008/02/080205100955.htm>.
Imperial College London. (2008, February 11). 'T-ray' Breakthrough Signals Next Generation Of Security Sensors. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2008/02/080205100955.htm
Imperial College London. "'T-ray' Breakthrough Signals Next Generation Of Security Sensors." ScienceDaily. www.sciencedaily.com/releases/2008/02/080205100955.htm (accessed July 29, 2014).

Share This




More Matter & Energy News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Lithium Battery 'Holy Grail' Could Provide 4 Times The Power

Newsy (July 28, 2014) Stanford University published its findings for a "pure" lithium ion battery that could have our everyday devices and electric cars running longer. Video provided by Newsy
Powered by NewsLook.com
The Carbon Trap: US Exports Global Warming

The Carbon Trap: US Exports Global Warming

AP (July 28, 2014) AP Investigation: As the Obama administration weans the country off dirty fuels, energy companies are ramping-up overseas coal exports at a heavy price. (July 28) Video provided by AP
Powered by NewsLook.com
Shipping Crates Get New 'lease' On Life

Shipping Crates Get New 'lease' On Life

Reuters - Business Video Online (July 25, 2014) Shipping containers have been piling up as America imports more than it exports. Some university students in Washington D.C. are set to get a first-hand lesson in recycling. Their housing is being built using refashioned shipping containers. Lily Jamali reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Highest Train Turns 80 in French Pyrenees

Europe's Highest Train Turns 80 in French Pyrenees

AFP (July 25, 2014) Europe's highest train, the little train of Artouste in the French Pyrenees, celebrates its 80th birthday. Duration: 01:05 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins