Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Tiny infrared laser holds promise as weapon against terror

Abstract:
Researchers have demonstrated a specialized diode laser that holds promise as a weapon of defense in both civilian and military applications

Tiny infrared laser holds promise as weapon against terror

Evanston, IL | August 05, 2005

The difficulty of detecting the presence of explosives and chemical warfare agents (CWAs) is once again all too apparent in the news about the London bombings.

In a significant breakthrough, researchers at Northwestern University’s Center for Quantum Devices have demonstrated a specialized diode laser that holds promise as a weapon of defense in both civilian and military applications. Once optimized, the tiny laser could quickly detect explosives and CWAs early and warn against possible threats.

The Northwestern team, led by center director Manijeh Razeghi, became the first to create a quantum cascade laser (QCL) that can operate continuously at high power and at room temperature with an emission wavelength of 9.5 microns and a light output of greater than 100 milliwatts.

Existing standard diode lasers, such as those used to read compact discs or barcodes, do not operate effectively in the longer wavelengths that are required to detect CWAs. The challenge for researchers around the world has been to develop a portable laser that operates in the far-infrared (wavelengths of 8 to 12 microns). Every chemical has a unique “fingerprint” because it absorbs light of a specific frequency, and most CWAs fall in the 8 to 12 micron region.

“Our achievement is critical to building an extremely sensitive chemical detection system,” said Razeghi, Walter P. Murphy Professor of Electrical and Computer Engineering. “One of the key elements in a successful system is the laser source. Both mid- and far-infrared diode lasers need to operate at room temperature, have high power -- greater than 100 milliwatts -- and be extremely small in order to keep the system portable. We have now demonstrated such a laser in the far-infrared wavelength range.”

This research is part of a three-year program called Laser Photoacoustic Spectroscopy (LPAS) funded by the Defense Advanced Research Projects Agency (DARPA). The goal of the program is to develop a man-portable system that can warn against a large number of potential threats using mid- and far-infrared diode lasers. Once optimized, such lasers would be a very reliable means of detecting explosives and chemical warfare agents while distinguishing them from benign chemicals present in the atmosphere.

During the next two years Razeghi and her team will work to put together a detection system based on the center’s far-infrared laser. The system will then be evaluated by DARPA for use by the military.

Northwestern is a world leader in high-power QCL research. The Center for Quantum Devices was the first university research lab in the world to successfully grow, fabricate and test quantum cascade lasers back in 1997. By utilizing quantum mechanical design principles and advanced crystal growth techniques, the QCL is able to demonstrate high-power and high-temperature operation.

After the initial demonstration of room-temperature pulsed lasers in 1997, the primary efforts of Razeghi and her colleagues over the past several years have been to increase the laser’s operating temperature, power output and efficiency in order to achieve the continuous operation necessary for sensitive chemical analysis.

In 2003 the center was the first to demonstrate high-power mid-wavelength infrared continuous wave QCLs operating above room temperature. (Like the far infrared, standard diode lasers cannot access this mid-infrared range.) At present, individual devices with output powers of several hundred milliwatts have been demonstrated in the 3 to 5 microns wavelength range.

Razeghi’s research is supported by the Defense Advanced Research Projects Agency, U.S. Air Force Office of Scientific Research, the Army Research Office and the Office of Naval Research.

####

Contact:
Megan Fellman (847) 491-3115 fellman@northwestern.edu

Source contact:
Manijeh Razeghi
847-491-7251
razeghi@ece.northwestern.edu

Copyright © Northwestern University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Possible Futures

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanozirconia Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Self-Healing Nano Anti-rust Coatings Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Nano Spray Instrument Market 2015 - Global Industry Survey, Analysis, Size, Share, Outlook and Forecast to 2020 July 31st, 2015

Sensors

Quantum states in a nano-object manipulated using a mechanical system August 3rd, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Gold-diamond nanodevice for hyperlocalised cancer therapy: Gold nanorods can be used as remote controlled nanoheaters delivering the right amount of thermal treatment to cancer cells, thanks to diamond nanocrystals used as temperature sensors August 1st, 2015

Advances and Applications in Biosensing, Sensor Power, and Sensor R&D to be Covered at Sensors Global Summit August 1st, 2015

Announcements

Proving nanoparticles in sunscreen products August 4th, 2015

Global Carbon Nanotubes Industry 2015: Acute Market Reports August 4th, 2015

Nanoparticles Give Antibacterial Properties to Machine-Woven Carpets August 4th, 2015

Diagnosis of Salmonella Bacterium-Caused Food Poisoning by Biosensors August 3rd, 2015

Homeland Security

Nanopaper as an optical sensing platform July 23rd, 2015

Iranian Scientists Design Nano Device to Detect Cyanogen Toxic Gas June 23rd, 2015

New sensing tech could help detect diseases, fraudulent art, chemical weapons June 1st, 2015

UCLA nanoscientists are first to model atomic structures of three bacterial nanomachines: Cryo electron microscope enables scientists to explore the frontiers of targeted antibiotics April 21st, 2015

Military

Self-assembling, biomimetic membranes may aid water filtration August 1st, 2015

Take a trip through the brain July 30th, 2015

Sol-gel capacitor dielectric offers record-high energy storage July 30th, 2015

Reshaping the solar spectrum to turn light to electricity: UC Riverside researchers find a way to use the infrared region of the sun's spectrum to make solar cells more efficient July 27th, 2015

NanoNews-Digest
The latest news from around the world, FREE



  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project