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.


 
 

 

Headlines July 31, 2015

News: Carter: Military leaders could arm more troops at home – Following the recent fatal shooting of four Marines and a sailor in Tennessee, Defense Secretary Ash Carter is ordering the military services to consider new policies that would enhance security for troops at home, including potentially arming more personnel.   Business: DOD weighs supplier base,...
 
 

News Briefs July 31, 2015

U.S. delivering eight newer F-16 warplanes to Egypt The United States Embassy in Cairo says the U.S. is delivering eight newer F-16 warplanes to Egypt as part of an ongoing military support package. It says in a July 30 statement that the aircraft, of the current Block 52 production variant, will be flown in from...
 
 
Lockheed Martin photograph

Lockheed Martin successfully tests design changes for Orion spacecraft’s fairing separation system

Lockheed Martin photograph A protective panel for Orion’s service module is jettisoned during testing at Lockheed Martin’s Sunnyvale, California facility. This test series evaluated design changes to the spacecraft’s fair...
 

 

Australian company to provide parts for initial production of Triton UAS

Northrop Grumman has awarded the first Australian supplier contract for the U.S. Navy’s MQ-4C Triton unmanned aircraft system initial production lot to Ferra Engineering. Brisbane-based Ferra Engineering will manufacture mechanical sub-assemblies for the first four Triton air vehicles including structural components. “At Northrop Grumman it’s very important to not only develop...
 
 
Boeing photograph

CH-46 ‘Phrog’ makes its last hop

Boeing photograph The CH-46 Sea Knight helicopter commonly known as the “Phrog,” is set to retire and to be flown one last time by Reserve Marine Medium Helicopter Squadron (HMM) 774 on Aug. 1. The CH-46 Sea Knight is a med...
 
 

Insitu awarded LRIP Lot IV RQ-21A Blackjack Systems contract

Under the terms of its latest contract, Insitu will build six RQ-21A Blackjack systems for the U.S. Navy and Marine Corps. The $78-million Small Tactical Unmanned Aircraft Systems Lot IV Low Rate Initial Production contract is the latest event in the program’s progression toward the Initial Operational Test and Evaluation phase.   “This award will...
 




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=""> <s> <strike> <strong>