14 DAY TRIAL // Currently, producing X-rays is a fairly difficult process, which requires some impressive and expensive facilities in order to run smoothly. For a long time, researchers have tried to eliminate this aspect of scientific research, and it would now appear that scientists at the Max Planck Institute for Quantum Optics, in Garching, Germany, have managed to find a new way of generating the radiation. They have built a smaller, but very powerful, X-ray source, which is able to fit on a tabletop. Such an innovation could bring advanced science to many laboratories around the world, Nature News reports.
Creating high-quality, X-ray images is very difficult to accomplish. Oftentimes, scientists want to obtain pictures that cannot be produced by the machines available at medical or research institutions. When this happens, they turn to synchotrons, large particle accelerators, which spin electrons around a magnet-laden ring. As they spin, the particles naturally emit high-quality, X-ray radiation, suitable for accurate observations. In the new German approach, the need for synchotrons is eliminated.
The researchers took a small hydrogen gas cell, and then shone a very brief and very powerful light directly at its core. The role of the short, 37-femtosecond laser pulse was to attempt to dislodge electrons off their orbits around the hydrogen nuclei. But, when electrons depart hydrogen, the atoms turn into ions with a positive charge, which attract the particles back to their orbits. However, this oscillation triggers what is called a wave. Out of all the electrons that are stricken by the laser, only a few make it out, and the way they avoid snapping back to their initial states is by riding this wave.
They essentially look like surfers, moving with the ensuing wave. In their path, magnetic lenses focus them, and then channel them through a second series of magnets, where they are made to “wiggle” back and forth. During this stage, the electrons' movements cause low-energy, 18-nanometer-wavelength X-rays to be released, the science team reports in the latest issue of the respected scientific journal Nature Physics.
The resulting particle accelerator can fit on a large tabletop, its creators say. The laser source must, however, rest on a different table. Still, this is a remarkable improvement from a synchotron the size of a large building, they add. “It is exciting. I don't think anybody really doubted it could be done. But they've actually shown that the beam quality can be fairly high,” Duke University Dean of Engineering Tom Katsouleas says.