Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Diode laser could be vital for safeguarding aircraft

05.09.2006
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.

Despite their name, heat-seeking missiles actually seek a characteristic infrared light given off by hot objects. Though invisible to the human eye, tiny detectors inside the missiles can detect this infrared light and use it for guidance.

To ensure the safety of aircraft, infrared countermeasure (IRCM) systems are used to confuse or blind the detectors. These systems require a high-power light source that can emit light at the correct wavelength. While various existing light sources may be able to succeed in disrupting the detectors, most are based on technology that is both bulky and expensive. Therefore, only a few military aircraft are now protected by IRCM systems. Developing a compact and inexpensive infrared light source will allow for widespread use of IRCMs, but it has proven to be a significant technical challenge.

A new type of diode laser, called the quantum cascade laser (QCL), may eventually change this situation. Diode lasers are inherently compact and suitable for mass-production, which has led to their widespread and low-cost use in everyday products, including CD and DVD players.

The Center for Quantum Devices (CQD) at Northwestern University, led by Manijeh Razeghi, Walter P. Murphy Professor of Electrical and Computer Engineering, has recently made great strides in laser design, material growth and laser fabrication that have greatly increased the output power and power conversion efficiency of QCLs. The center has now demonstrated individual lasers emitting at wavelengths of 3.8 and 4 microns, capable of up to 1.6 watts of continuous output power at cryogenic temperatures. These lasers have a threshold current density of less than 400 A/cm2 and a power conversion efficiency of 10 percent.

With further development, the researchers at CQD hope to use laser arrays to achieve a continuous output of 10 watts or more. At this wavelength and power level, the lasers could be extremely useful for aircraft protection.

Another significant breakthrough is the ability to operate these 3.8 and 4 micron lasers at room temperature. Room temperature continuous-wave operation has been demonstrated from the same devices with up to 150 milliwatts of output power. This room temperature development makes the lasers attractive for other applications, including early detection of toxic industrial chemicals, explosives and chemical warfare agents.

Megan Fellman | EurekAlert!
Further information:
http://www.northwestern.edu

More articles from Physics and Astronomy:

nachricht New thruster design increases efficiency for future spaceflight
16.08.2017 | American Institute of Physics

nachricht Tracking a solar eruption through the solar system
16.08.2017 | American Geophysical Union

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: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>