Jefferson Lab free electron laser undergoing major upgrade to increase power and wavelengths

July 03, 2002

On track and on time: That's the message from Fred Dylla, Jefferson Lab's Free-Electron Laser (FEL) program manager, concerning the ongoing upgrade of the most powerful device of its kind in the world. In all, some 50 staff and contractors are working 50-hour weeks to complete the FEL upgrade by October 2002. All the physical elements are slated to be connected by October 1, with recommissioning planned to take place in stages throughout 2003.

Engineers plan to install a new injector that will produce twice the amount of electron beam than is currently possible. The FEL's upgraded "wiggler" will double the fraction of electron-beam energy converted to laser light. Two additional cryomodules will be added to the FEL linear accelerator line, effectively quadrupling system energy from the current 40 million electron volts, or MeV, to 160 MeV. Laser power will surge at least 10-fold, to 10 kilowatts, and may eventually peak near 20 kilowatts.

When all is said and done, nearly the entire FEL will consist of new or upgraded components. "It's basically 90 percent a new machine," Dylla says. "We're keeping the injector and one cryomodule. But the injector will be substantially modified. And the linac will be enhanced."

Perhaps most importantly, researchers will literally be able to turn a knob in order to select different frequencies of light. This "tunability" is of crucial importance for materials research, but also helps scientists better understand the behavior of particles at the atomic level and below.

"Tunability for exploration is what people want," says Gwyn Williams, FEL basic research program manager. "It's about finding out how materials behave at different wavelengths of light. Because atoms are joined by chemical bonds, they act like springs. Now we can make those springs bounce up and down. In effect, we can hit any note and then watch what happens when we do."

A variety of companies are interested in the FEL's commercial potential. Thus far, FEL proof-of-concept experiments have included investigations of chemical-vapor deposition, a technique used to produce high-quality coatings and thin films for electronics and metals, as well as the effects of FEL processing on nylon, polyester and a class of materials known as polyimides. The Lab's FEL has also been able to create in bulk ultrasmall but very strong structures known as carbon nanotubes, which could eventually be the heart of minuscule next-generation computers, as well as structural components for aircraft and automobiles. The FEL can also be used to change the surface properties of food packaging, making it more resistant to microbes and food spoilage.

Another key enhancement will be the addition of an ultraviolet "sidetrack": a portion that will be capable of producing UV light for experiments. When complete, the sidetrack will enable the production of one kilowatt of UV light -- 1,000 times the capability of the one-watt devices commonly in use at other laboratories.
-end-
The bulk of the FEL upgrade funding is coming from the U.S. Navy -- $13.5 million -- and the U.S. Air Force -- $4.9 million. Additional monies have been provided by the state of Virginia and NASA. Once fully operational, the FEL is expected to be supported by research grants from the federal and state governments and by projects commissioned by industrial interests.

DOE/Thomas Jefferson National Accelerator Facility

Related Electron Articles from Brightsurf:

Attosecond boost for electron microscopy
A team of physicists from the University of Konstanz and Ludwig-Maximilians-Universit√§t M√ľnchen in Germany have achieved attosecond time resolution in a transmission electron microscope by combining it with a continuous-wave laser -- new insights into light-matter interactions.

Understanding electron transport in graphene nanoribbons
New research published in EPJ Plus aims to better understand the electron transport properties of graphene nanoribbons (GNRs) and how they are affected by bonding with aromatics - a key step in designing technology such as chemosensors.

Efficient valves for electron spins
Researchers at the University of Basel in collaboration with colleagues from Pisa have developed a new concept that uses the electron spin to switch an electrical current.

Measuring electron emission from irradiated biomolecules
Through a study published in EPJ D, researchers have successfully determined the characteristics of electron emission when high-velocity ions collide with adenine - one of the four key nucleobases of DNA.

Exploring mass dependence in electron-hole clusters
A study published in EPJ B reveals that the behaviour of one type of three-particle cluster displays a distinct relationship with the ratio between the masses of its particles.

Attosecond control of an atomic electron cloud
Researchers at SAGA Light Source, the University of Toyama, Hiroshima University and the Institute for Molecular Science have demonstrated a method to control the shape and orientation of an electron cloud in an atom by tuning the attosecond spacing in a double pulse of synchrotron radiation.

Electron correlations in carbon nanostructures
Graphene nanoribbons are only a few carbon atoms wide and have different electrical properties depending on their shape and width.

The fast dance of electron spins
Metal complexes show a fascinating behavior in their interactions with light, which for example is utilized in organic light emitting diodes, solar cells, quantum computers, or even in cancer therapy.

Novel mechanism of electron scattering in graphene-like 2D materials
Suggesting an unconventional way to manipulate the properties of 2D materials in the presence of a Bose-Einstein condensate, and an alternative strategy to design high-temperature superconductors.

Switching electron properties on and off individually
Electrons have different properties - and they all can be used to create order in solid objects.

Read More: Electron News and Electron Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.