By firing a femtosecond laser - a laser that generates light pulses with durations as short as 100 trillionth of a second - through a gas-filled tube called a waveguide, they were able to create more efficient "laser-like" beams in regions of the spectrum that were previously inaccessible.
The wavelength region over which they generate this "soft" x-ray light efficiently is called the "water-window" region, an important region for biological imaging, according to physics Professor Margaret Murnane. She also is a fellow of JILA, a joint institute of CU-Boulder and the National Institute of Standards and Technology.
The water window is an area in the spectrum where water is less absorbing than carbon, which means carbon absorbs more light and thus makes it easier to take images, according to Murnane. Current technology allows researchers to do work in this region, but requires a large-scale and expensive facility.
"With further work, this advance will make it possible to build a compact microscope for biological imaging that fits on a desktop," Murnane said. "Such microscopes could visualize processes happening within living cells, or perhaps even allow scientists to understand how pharmaceuticals function in detail."
A paper on the subject by graduate student Emily Gibson, physics Professor Henry Kapteyn, Murnane, Ariel Paul, Nick Wagner, Ra'anan Tobey, David Gaudiosi and Sterling Backus of the CU-Boulder department of physics and JILA appears in the Oct. 3 issue of the journal Science. Ivan Christov of Sofia University in Bulgaria, Andy Aquila and Eric Gullikson of the Lawrence Berkeley National Laboratory and David Attwood of the University of California at Berkeley and the Lawrence Berkeley National Labora
Contact: Henry Kapteyn
University of Colorado at Boulder