It was thought that it would take an atomic bomb to produce enough power to generate an X-ray laser, but a team of boffins have fired one from a table-top box of tricks.
X-ray lasers need astonishing amounts of power and huge equipment to create extremely short-lived yet coherent beams with a wavelength in the tens of nanometers - dozens of times shorter than that of visible light. But now a cross-continental team has produced a smaller cost-effective alternative and published the test results in the Science journal today.
The scientists made the breakthrough using a phenomenon called high-harmonic generation: atoms are shot by a specific laser pulse that causes their electrons to tear away and then return to collide with the atoms and emit energy right across the electromagnetic spectrum.
The researchers were able to focus intense pulses of infrared into a high-pressure noble gas chamber to kickstart this process and produce a rainbow of radiation that - for the first time ever - included a stable X-ray beam.
Applications of these stupidly high-resolution femtosecond lasers include the study of biological cell structures and chemical reactions.
Deborah Jackson of America's Engineering Research Center, which is funding the project, said: "Thirty years ago, people were saying we could make a coherent X-ray source, but it would have to be an X-ray laser, and we'd need an atomic bomb as the energy source to pump it.
"Now, we have these guys who understand the science fundamentals well enough to introduce new tricks for efficiently extracting energetic photons, pulling them out at X-ray wavelengths - and it's all done on a table-top." ®