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In a recent advancement that could significantly shrink particle accelerators for science and medicine, researchers utilized a laser to accelerate electrons 10 times higher/faster than traditional technology in a nanostructured glass chip, equivalent to the size of a grain of rice.

This breakthrough feat was reported in Nature by a team including scientists from the U.S. Department of Energy's (DOE) SLAC National Accelerator Laboratory and Stanford University.

"We still have a number of challenges before this technology becomes practical for real-world use, but eventually it would substantially reduce the size and cost of future high-energy particle colliders for exploring the world of fundamental particles and forces. It could also help enable compact accelerators and X-ray devices for security scanning, medical therapy and imaging, and research in biology and materials science,” said SLAC physicist who led the experiments, Joel England.

Since it utilizes commercial lasers and cost-effective, mass-production methods, which researchers trust will lead to new developments and advancements for "tabletop" accelerators.

At maximum potential, the new "accelerator on a chip" could formidably compete with and even surpass the accelerating power of SLAC's 2-mile-long linear accelerator in just 100 feet, and deliver a million more electron pulses per second.Accelerator on chip could Lead to New Innovations of Smaller Cost-effective Devices for Medicine

The first showcase attained an acceleration gradient, or amount of energy achieved per length, of 300 million electronvolts per meter. That is approximately 10 times greater than the acceleration supplied by the current SLAC linear accelerator.

"Our ultimate goal for this structure is 1 billion electronvolts per meter, and we're already one-third of the way in our first experiment," said Stanford Professor and principal investigator for this research, Robert Byer.

Nowadays, accelerators utilize microwaves to amplify the energy of electrons. Researchers have been searching for more cost-effective substitutes and this new development which employs ultrafast lasers to drive the accelerator, is a prime contender.

Particles are usually accelerated in two stages. First they are amplified to nearly the speed of light. Then any additional acceleration increases their energy, but not their speed; this is where it becomes challenging.

In the accelerator-on-a-chip experiments, electrons are first accelerated to near light-speed in a traditonal accelerator. Then they are focused into a tiny, half-micron-high channel within a fused silica glass chip which measures around half a millimeter long. The channel had been designed with precisely spaced nanoscale ridges. Infrared laser light shining on the design produces electrical fields that interact with the electrons in the channel to raise their energy.

Turning the accelerator on a chip into a full-fledged tabletop accelerator will involve a more condensed way to get the electrons up to speed before they enter the device.

A collaborating research team in Germany, led by Peter Hommelhoff at the Max Planck Institute of Quantum Optics, has been searching for an appropriate resolution. While at the same time it reports in Physical Review Letters its accomplishment in using a laser to accelerate lower-energy electrons.

Applications for these new particle accelerators would go well beyond particle physics research. Byer said laser accelerators could drive compact X-ray free-electron lasers, comparable to SLAC's Linac Coherent Light Source, that are all-purpose tools for a wide range of research.

Another potential application would be a small, portable X-ray sources to advance medical care for people injured in combat, as well as offer more affordable medical imaging for hospitals and laboratories. This is one of the many goals of the Defense Advanced Research Projects Agency's (DARPA) Advanced X-Ray Integrated Sources (AXiS) program, which partly funded this research. Primary funding came from the DOE's Office of Science.

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