Scientists Beaming Over Laser

Powerful light debuts at Jefferson Lab

The way they were shouting and high-fiving each other, you might have taken them for Bulls fans watching Sunday's NBA finale.

But what the scientists at Jefferson Lab were watching on the TV screen Wednesday required some explanation to appreciate: a circular light at the top of the screen, just above a meter with numbers that jumped up and down. The higher the numbers went, the more excited the scientists got.

"Isn't that gorgeous?" George Neil asked the others.

The light the scientists were watching was produced by Jefferson Lab's free-electron laser; the meter was measuring the light's power in watts. Four years in the making, the laser produced its first light on Monday. On Wednesday afternoon, with the scientists glued to the set, the laser exceeded the lab's goal of 100 watts - some 10 times more powerful than any other laser of its type.

"We're just giddy," said Fred Dylla, manager of the free-electron laser program.

Whether this milestone will someday be considered historic remains to be seen. Its designers say the laser can be used in a wide range of manufacturing processes, from precision cutting to physically altering the surfaces of materials like ceramics or plastics. They say a new type of high-tech industry could sprout on the Peninsula, as companies come to use the laser or build their own.

This vision begins to take shape in a few weeks, when the laser will be ready for its first few experiments. DuPont wants to see if the laser light can be used to give polyester fiber a more natural feel. Three companies - Armco Steel, Virginia Power and Northrop Grumman - will test the laser's use in treating metals to improve their resistance to wear and corrosion.

The laser is a spinoff project for Jefferson Lab. With close to $70 million a year from the U.S. Department of Energy, the lab's main mission is to probe the basic structure of the atom using a high-energy electron beam. The equipment and expertise used to create that beam were put to work building the laser.

The laser is in the basement of a 20,000-square-foot building. On the main floor upstairs is the laser beam control room and six laboratories into which the laser light can be directed with mirrors.

Neil, Dylla and about a half-dozen others watched the TV screen in the control room Wednesday afternoon. Neil wore a headset, through which he communicated with Court Bohn and Dave Douglas, scientists who actually operated the laser from a room in another building.

The scientists were not so much excited because their laser worked but that it worked so well so quickly, Dylla said. Other free-electron lasers have taken weeks or months to start up, and the Jefferson Lab scientists planned on two weeks of adjusting and readjusting until they could reach 100 watts. They peaked Wednesday afternoon at 155 watts.

At 100 watts, the laser light is 150,000 times more powerful than lasers in CD players or supermarket scanners, Dylla said. After some more adjustments this fall, the scientists plan to up the free-electron laser to 1,000 watts.

The power means more than brute laser strength. A focused laser beam with 50 watts of power can cut through almost anything, but with more power comes speed, Dylla said. Where a conventional laser can treat a square yard of polyester in an hour, the free-electron laser can treat several square yards per second, making it more practical to do on a large scale, he said.

By Wednesday afternoon, the scientists began thinking of toasting their achievement. Lemonade? Club soda? Department of Energy rules forbid alcohol in the laser building. Eventually, though, it was decided to move the celebration to the nearby Applied Research Center.

"That's so we wouldn't have to get special permission to open a bottle of champagne," Dylla said.

For downloadable photos and additional text, please consult http://www.jlab.org/FEL/FELpics/FirstLight/FirstLight.html.