Synchrotron X-rays produce higher quality images with lower doses of radiation, but they are about the size of a college campus and staggeringly expensive; researchers may have created a significantly more compact device that could produce these images in a hospital.
"Our hope is that this new technology will lead to applications that benefit both science and society," Nathan Powers, a Ph.D. student and first author of the journal article, said in an Azooptics article.
Lead researcher of the project Physics professor Donald Umstadter, director of the Extreme Light Laboratory compared the breakthrough to the transition from huge supercomputers to smaller models for personal use.
This downsized device could be used for a number of new applications such as to detect nuclear materials contained in shielded containers or allowing scientists to look at "extremely fast reactions" that remain undetected with today's technology.
Synchrotron X-ray light sources have been around for 60 years, and over that time they have actually grown in size. These large devices are still being built, mainly in Brazil and Australia.
In today's synchrotron machines "electrons are accelerated to extremely high energy and then made to change direction periodically, leading them to emit energy at X-ray wavelength." Magnets are generally used to make the electrons change directions.
The research team tried replacing the electron accelerator and magnets with powerful lasers. The laser was pointed at a gas jet, which produced relativistic electrons. Once the electrons were created the team turned the attention of another laser towards them; this caused the electrons to vibrate violently and emit synchrotron X-rays.
"The X-rays that were previously generated with compact lasers lacked several of the distinguishing characteristics of synchrotron light, such as a relatively pure and tunable color spectrum," Umstadter said. "Instead, those X-rays resembled the 'white light' emitted by the sun."
Very few modern devices are capable of producing such high photon energy. The key to the study's success was efficiently colliding the two laser beams.
"Our aim and timing needed to be as good as that of two sharpshooters attempting to collide their bullets in midair," Umstadter said. "Colliding our 'bullets' might have even been harder, since they travel at nearly the speed of light."
