 |
Tiny infrared laser holds promise as weapon against terror
August 08, 2005EVANSTON, Ill. -- 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 four-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.
Northwestern University
Related Chemical Warfare Agents Current Events and Chemical Warfare Agents News Articles
New substances 15,000 times more effective in destroying chemical warfare agents
In an advance that could be used in masks to protect against nerve gas, scientists are reporting development of proteins that are up to 15,000 times more effective than their natural counterpart in destroying chemical warfare agents.
New test could help track down and prosecute terrorists who use nerve gas and other agents
Scientists are reporting development of a first-of-its-kind technology that could help law enforcement officials trace the residues from terrorist attacks involving nerve gas and other chemical agents back to the companies or other sources where the perpetrators obtained ingredients for the agent.
Scientists create natural Alzheimer's-fighting compound in lab
Scientists at Yale University have developed the first practical method to create a compound called huperzine A in the lab.
OSU chemist developing solution to nerve agent exposure
Scientists are working to develop a new drug that will regenerate a critical enzyme in the human body that "ages" after a person is exposed to deadly chemical warfare agents.
Low-dose exposure to chemical warfare agent may result in long-term heart damage
New research found that the pattern of heart dysfunction with sarin exposure in mice resembles that seen in humans. Sarin is a chemical warfare agent belonging to class of compounds called organophosphates - the basis for insecticides, herbicides and nerve agents.
Structure of enzyme against chemical warfare agents determined
The enzyme DFPase from the squid Loligo vulgaris, is able to rapidly and efficiently detoxify chemical warfare agents such as Sarin, which was used in the Tokyo subway attacks in 1995.
MIT gas sensor is tiny, quick
Engineers at MIT are developing a tiny sensor that could be used to detect minute quantities of hazardous gases, including toxic industrial chemicals and chemical warfare agents, much more quickly than current devices.
Biosensor sniffs out explosives
Temple University School of Medicine researchers have developed a new biosensor that sniffs out explosives and could one day be used to detect landmines and deadly agents, such as sarin gas, according to a paper in the June issue of Nature Chemical Biology.
Diode laser could be vital for safeguarding aircraft
Terrorists can strike anywhere, at any time, and aircraft, both military and civilian, are targets for heat-seeking missiles, one of many tactics in use by groups hostile to the United States.
Sandia's rapidly deployable chemical detection system tested at McAfee Stadium
Baseball fans cheering on their beloved Oakland A's in a recent homestand may have been happy about the team's play, but the best news for those visitors to McAfee Stadium didn't take place on the field and couldn't be noticed by even the most observant spectators.
More Chemical Warfare Agents Current Events and Chemical Warfare Agents News Articles
 |
A Laboratory History of Chemical Warfare Agents by Jared Ledgard (Author) A Laboratory History of Chemical Warfare Agents is a revolutionary new book discussing the laboratory preparation of some of the most interesting toxic substances known to man. However broad the field may be, this book is an invaluable collection of nearly 100 years of chemical warfare research and history. From the researcher to the student or just plain novice, the information contained herein will change the way you think about warfare agents and their properties. The book is a valuable educational tool designed to give the reader a full picture of the world of chemical warfare agents. NOTE TO CUSTOMERS: This book has been renamed from the Preparatory Manual of Chemical Warfare Agents, to A Laboratory History of Chemical Warfare Agents. |
 |
Chemical Warfare Agents: Toxicology and Treatment by Dr Timothy T. Marrs (Editor), Robert L. Maynard (Editor), Frederick Sidell (Editor) Chemical Warfare Agents, Second Edition has been totally revised since the successful first edition and expanded to about three times the length, with many new chapters and much more in-depth consideration of all the topics. The chapters have been written by distinguished international experts in various aspects of chemical warfare agents and edited by an experienced team to produce a clear review of the field.The book now contains a wealth of material on the mechanisms of action of the major chemical warfare agents, including the nerve agent cyclosarin, formally considered to be of secondary importance, as well as ricin and abrin. Chemical Warfare Agents, Second Edition discusses the physico-chemical properties of chemical warfare agents, their dispersion and fate in the environment,... |
 |
Handbook of Toxicology of Chemical Warfare Agents by Ramesh C. Gupta (Editor) This exciting book covers every aspect of deadly toxic chemicals used as weapons of mass destruction and employed in conflicts, warfare and terrorism. Including findings from experimental as well as clinical studies, this one-of-a-kind handbook is prepared in a very user- friendly format that can easily be followed by students, teachers and researchers, as well as lay people. Stand alone chapters on individual chemicals and major topics allow the reader to easily access required information without searching through the entire book. This is the first book that offers in-depth coverage of individual toxicants, target organ toxicity, major incidents, toxic effects in humans, animals and wildlife, biosensors, biomarkers, on-site and laboratory analytical methods, decontamination and... |
 |
Handbook of Chemical and Biological Warfare Agents, Second Edition by D. Hank Ellison (Author) Extensively revised and updated, this second edition of the bestselling Handbook of Chemical and Biological Warfare Agents goes well beyond the “dirty thirty” commonly discussed agents and provides rapid access to a wide range of agents that can be used as weapons. This edition incorporates additional classes of agents, expands existing classes, and increases the number of agents described. Expanding the scope of the original, this edition is rich with scientific data and provides more information on the chemical, physical, and biological properties of these agents and their health effects. Highly organized and cross-referenced to provide instant access to the most authoritative data, this handbook is divided into classes based on the common military groupings of chemical,... |
 |
The Preparatory Manual of Chemical Warfare Agents Third Edition by Jared Ledgard (Author) The Preparatory Manual of Chemical Warfare Agents Third Edition is a massive upgrade to "A Laboratory History of Chemical Warfare Agents", and it's original title has been re-established. The book includes many upgraded information on existing warfare agents including updated molecular formulas, 3D molecules, and molecular data. This third edition includes brand new chapters and sections including a chapter discussing the complete preparation and data of nerve agent antidotes; a huge section on the preparation of potential and experimental warfare agents (nerve agents), including a valuable section and chapter on the complete preparation and data of nerve agent intermediates; a section and chapter on the complete preparation and data on the incapacitating agent BZ and military... |
 |
Compendium of Chemical Warfare Agents by Steven L. Hoenig (Author) Highly lethal chemicals may be the new weapons of choice among terrorist groups throughout the world. This is a grave concern for all First Responders and Emergency Management personnel. This book furnishes the critical information to deal with this threat and provides all the necessary information that First Responders, Hospitals, HazMat Teams, Fire and Rescue Services, and other First Responders need to know when dealing with dangerous chemical agents. |
 |
Handbook of Chemical and Biological Warfare Agents by D. Hank Ellison (Author) With terrorist groups expanding their weapons of destruction beyond bombs and bullets, chemical and biological warfare agents aren't merely limited to the battlefield anymore. In some cases, they are now being used on a new front: major metropolitan cities. And in the Handbook of Chemical and Biological Warfare Agents, emergency response personnel-from HazMat and Police SWAT teams to Explosive Ordinance Disposal units-will find a myriad of information on how to deal with such incidents involving dangerous chemical and biological agents. The 504-page book is formatted into a series of indices developed to facilitate rapid access to key information on chemical, biological and toxin agents, with each index cross-referenced to all others. The wealth of data not only include the... |
|
Manual of Explosives, Military Pyrotechnics, and Chemical Warfare Agents : Composition, Properties, Uses by Jules Bebie (Author) | |
 |
Handbook of Chemical and Biological Warfare Agent Decontamination by George O. Bizzigotti (Author), Richard P. Rhoads (Author), Stephen J. Lee (Author) Chemical and biological warfare agents are continuing threats to the military on the battlefield as well as to civilians in the form of terrorist attacks. When material becomes contaminated with these agents, it must be decontaminated before it can be used or disposed of, and the extent of decontamination required will depend on the intended use. This book is a comprehensive overview of the scientific research and development that has been done chemical and biological agent decontamination technology in the US military. It begins with a section on the background of decontamination, which includes a chronological history of military research, an overview of the US Department of Defense decontamination principles and requirements, and a chapter that acts as a primer on chemical and... |
 |
Scorched Earth: Legacies of Chemical Warfare in Vietnam by Fred A. Wilcox (Author), Noam Chomsky (Introduction) Scorched Earth is the first book to chronicle the effects of chemical warfare on the Vietnamese people and their environment, where, even today, more than 3 million people—including 500,000 children—are sick and dying from birth defects, cancer, and other illnesses that can be directly traced to Agent Orange/dioxin exposure. Weaving first-person accounts with original research, Vietnam War scholar Fred A. Wilcox examines long-term consequences for future generations, laying bare the ongoing monumental tragedy in Vietnam, and calls for the United States government to finally admit its role in chemical warfare in Vietnam. Wilcox also warns readers that unless we stop poisoning our air, food, and water supplies, the cancer epidemic in the United States and other countries will only... |
| © 2013 BrightSurf.com |