Real-Time 3D X-Rays Could Soon Become Possible

As every doctor who ever operated inside a patient without actually seeing what they were doing can tell you, having a device that shows precisely what is happening in a non-intrusive manner could be the decisive advantage in saving a patient's life. For a long time, physicists have postulated that it could be possible to harness the power of X-rays to do just that, and that theory has been recently proven by a collaboration between the University of Nebraska-Lincoln (UNL) and two Russian research institutes.

The research will be able to give scientists more clues on how to generate and control coherent, high-powered X-rays, which could be used, for example, to show the insides of a patient in a 3D image, for use during a surgery. “This could be a contributor to a number of innovations,” UNL Physics and Astronomy Professor Anthony Starace, the lead researcher of the study, scheduled for publication in an upcoming issue of the respected scientific journal Physical Review Letters, explains.

The process the team investigated for their conclusions is known among experts as high-harmonic generation (HHG). High-energy lasers are used on atoms of gaseous elements of low-electron type, such as hydrogen, helium and neon. When the beam of stimulated light hits the electrons around these atoms, it forces them to vibrate at high speeds, which in turn unleashes large and powerful amounts of X-rays. These radiations can then be harnessed for medical purpose, for example.

However, the main problem with HHG is that, until now, it only offered limited results, in that the amount of obtained radiation was too low to serve any practical purpose. “Using longer wavelength lasers is another way to increase the energy output of the atoms. The problem is, the intensity of the radiation [the atoms] produce drops very quickly,” Starace further explains. To solve this issue, the team turned their attention to heavier gaseous elements, such as xenon, argon and krypton, which have more electrons around their protons, but which are rarer and more difficult to obtain.

The scientists learned that, by using longer wavelength lasers, they were able to drive collective electron oscillations in these heavier, multiple-electron atoms, which in turn emitted much larger amounts of X-rays, ready in sufficient amounts to be used for practical applications. “If you use these rare gases and shine a laser in on them, they'll emit X-Rays with an intensity that is much, much stronger. The atomic structure matters,” the expert adds.