Space

August 15, 2012

Ultrafast pulsed lasers … more than just a light show

A Navy ship at sea is surrounded by water, with nothing but its carrier group in site, and searches the skies for activity overhead. Isolated radars on each ship in the group scan independently of each other with limited effectiveness.

But consider if all of the ships’ radars could be coherently linked to function as one. Such a capability would improve the range and resolution of each radar system, making it possible to identify and characterize objects further away and with greater fidelity.

Conventional X-ray machines provide images of bones and organs that help doctors make crucial decisions regarding patient care. They cannot, however, resolve structures at the cellular level. Imagine having access to a table-top x-ray imager that could not only image a single cell, but also the nucleus, ribosomes and other components that make it up; and not only as a flat image, but in 3-D. Such information would be invaluable for testing responses to candidate drugs and discovering new treatments.

These two very different applications are not science fiction and could be enabled by the same basic technology: ultrafast, pulsed lasers operating at optical wavelengths.

These kinds of pulsed lasers are known as frequency combs because they are composed of thousands of individual laser lines, equally separated in frequency like the teeth of a comb. DARPA seeks to control the entire electromagnetic spectrum by using frequency combs to generate and engineer waves in the optical domain and then down or up-convert those waveforms to the desired wavelength. Such technology has many potential applications relevant to the Department of Defense, such as low phase noise microwave oscillators for secure communications, explosive and chemical agent detection, and the production of attosecond (10-18s) pulses for imaging the motion of electrons in complex materials.

Many of the techniques that underlie these applications have been demonstrated, but are currently unsuitable for practical use because they are restricted to a laboratory setting. DARPA’s Program in Ultrafast Laser Science and Engineering (PULSE) aims to enable synchronization, metrology and communications applications for DoD by advancing compact, high power and environmentally insensitive frequency comb technology, as well as the science underlying these applications. Achieving these goals will require input from researchers across a broad spectrum of disciplines. Potential proposers are encouraged to review and respond to the PULSE Broad Agency Announcement.

“PULSE is a basic research program initially focused on component technology. Our primary concern isn’t demonstrating a specific application, rather making these tools a reality at a practical scale by overcoming current obstacles like size and thermal management,” said Jamil Abo-Shaeer, DARPA program manager for PULSE. “The range of potential applications is enormous. Literally any technology that uses electromagnetic radiation could be impacted.”

Low phase noise microwave oscillators represent one potential application of the high frequency stability provided by optical frequency combs. Under PULSE, DARPA will pursue enabling technologies to reduce comb size. One possible approach involves recently demonstrated, chip-based optical frequency combs that were generated from micron-scale optical resonators. However, while such combs potentially offer a vast reduction in form-factor compared with conventional technology, they have yet to demonstrate the stability and bandwidth required for low phase noise microwave oscillator production.

At the other end of the spectrum, PULSE will explore how to capitalize on the high intensity obtainable from pulsed lasers for applications like x-ray imaging. PULSE aims to enhance the capabilities of tabletop, high-peak power, pulsed-laser driven x-ray generation techniques; these sources should produce high flux, coherent x-rays with wavelengths in the water-window (2.3 to 4.4 nm) for biological imaging applications. At present, these types of x-rays can only be generated by a few building-sized machines, thus limiting the range of applications.

As a fundamental research program, PULSE welcomes proposals from U.S. and international researchers and is expected to span over a five year time-scale. For detailed information, please review the BAA at: http://go.usa.gov/G71. Proposal abstracts are due by 4 p.m., EDT, Sept. 6, 2012. Full proposals are due by 4 p.m., EDT, Nov. 6, 2012.

 




All of this week's top headlines to your email every Friday.


 
 

 

News Briefs February 27, 2015

Ukraine will start pulling back heavy weapons in the east Ukraine’s military says it will start pulling back its heavy weapons from the front line with Russian-backed separatists as required under a cease-fire agreement. The Defense Ministry said in a statement Feb. 26 that it reserved the right to revise its withdrawal plans in the...
 
 

Northrop Grumman’s AstroMesh reflector successfully deploys for NASA’s SMAP satellite

The NASA Jet Propulsion Laboratory successfully deployed the mesh reflector and boom aboard the Soil Moisture Active Passive spacecraft, a key milestone on its mission to provide global measurements of soil moisture. Launched Jan. 31, SMAP represents the future of Earth Science by helping researchers better understand our planet. SMAP’s unmatched data capabilities are enabled...
 
 
NASA photograph by Brian Tietz

NASA offers space tech grants to early career university faculty

NASA photograph by Brian Tietz Tensegrity research is able to simulate multiple forms of locomotion. In this image, a prototype tensegrity robot reproduces forward crawling motion. NASA’s Space Technology Mission Director...
 

 
navy-china

USS Fort Worth conducts CUES with Chinese Navy

The littoral combat ship USS Fort Worth (LCS 3) practiced the Code for Unplanned Encounters at Sea (CUES) with the People’s Liberation Army-Navy Jiangkai II frigate Hengshui (FFG 572) Feb. 23 enhancing the professional ma...
 
 

AEGIS tracks, simulates engagement of three short-range ballistic missiles

The Missile Defense Agency and sailors aboard the guided-missile destroyers USS Carney (DDG 64), USS Gonzalez (DDG 66), and USS Barry (DDG 52) successfully completed a flight test involving the Aegis Ballistic Missile Defense weapon system. At approximately 2:30 a.m., EST, Feb. 26, three short-range ballistic missile targets were launched near simultaneously from NASA’s Wallops...
 
 

DOD seeks novel ideas to shape its technological future

The Defense Department is seeking novel ideas to shape its future, and officials are looking to industry, small business, academia, start-ups, the public – anyone, really – to boost its ability to prevail against adversaries whose access to technology grows daily. The program, called the Long-Range Research and Development Plan, or LRRDP, began with an...
 




0 Comments


Be the first to comment!


Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>