'Star Wars' Defense? Laser beams up a record
Navy plans for a "Star Wars"-like laser that could blast low-flying missiles and attacking aircraft or ships are moving closer to reality with a new record by the world's most powerful infrared, tunable laser.
The recently upgraded Thomas Jefferson National Accelerator Facility's Free Electron Laser hit the 10-kilowatt mark — 10,000 watts — last week in Newport News, sustaining a near-continuous beam for several hours, more than long enough to collect on two international bets.
A laser more than 1.5 million times more powerful than those used in CD players gets a lot of notice from other potential high-tech users. College of William and Mary engineer Brian Holloway says the souped-up Free Electron Laser, or FEL, will do for his laser studies of churning out carbon nanotubes what the assembly line did for the Model T.
That research will start this fall, alongside experiments by the Office of Naval Research on how effectively the laser can burn and how well it will function in the moist atmosphere at sea.
The Office of Naval Researchis looking into whether the Jefferson Lab's FEL can be powered up even more. The goal is to determine whether an even-more powerful FEL operating at 100 kW could be turned into a defense system that can shoot down an incoming missile or disable a small boatload of terrorists before it can pull close to a Navy ship.
The project is far from deployment; for one thing, adapting FEL as a defense weapon would require an all-electric ship (which is under consideration by the Navy). But the Jefferson Lab's recent performance promotes the FEL-as-weapon out of the realm of science fiction.
"The U.S. has a technology edge right now in Free Electron Laser technology," Quentin Saulter, who manages the Office of Naval Research's FEL project, said yesterday.
The second-most-powerful laser of its kind is a Japanese one that puts out 25 watts. There are roughly 50 FELs around the world, used mostly for scientific research. Some, such as those at Vanderbilt and Duke universities, are used for medical applications.
In 1999, the Jefferson Lab site hit the 1 kW mark, making the Navy as well as the Air Force and Army sit up and take notice of the goings-on in Newport News.
Over the past four years, the Navy has contributed more than $21.5 million and the Air Force $10 million to juice the laser. The state of Virginia and the National Aeronautics and Space Administration also contributed to the new and improved $44 million FEL.
"It's a one-of-a-kind machine," said the Jefferson Lab's FEL program manager, Fred Dylla.
"People wait a lifetime for this kind of stuff," Holloway said of the milestone.
Scaling up the FEL is still more art than science, as the laser has nearly 20,000 components that have to work properly and precisely, Dylla said.
"You have to live with it awhile," Dylla said. "Some people have said that if you work with your machine and love it enough, it'll do what you want. That sounds anthropomorphic, but the machine takes on a certain personality that you get to know."
When the earlier version of the Jefferson Lab's FEL went online in 1998, it produced 155 watts. The laser went on to set new records for power, building up to 1 kilowatt.
That encouraged the lab to take apart the laser and upgrade its capability to 10 kW in the infrared spectrum and add a new sideline, ultraviolet light, whose components Dylla hopes to complete by next summer.
When completed, the refurbished FEL, which can be "tuned" or set to various specific wavelengths, will cover the spectrum from roughly 14 microns to one-quarter micron. The human eye sees only light at roughly 0.7 microns.
Laser is short for "light amplification by stimulated emission of radiation." A laser beam is a concentrated beam of light confined to a single wavelength.
Companies such as DuPont, 3M and Dominion Virginia Power are interested in the Jefferson Lab's FEL for its precise methods of cutting and altering the surface of materials. They're studying ways to make durable polymer fabrics for clothing and carpeting; cheap, easily recyclable beverage and food packaging; and corrosion-resistant metals with increased toughness.