The mini-accelerator could be a big boon in the medical industry, especially for cancer research. A magnified image of a section of the accelerator on a chip. (Image credit: Stanford University)
High power particle accelerators play a large role in the scientific community. They’re commonly used for scientific investigations, like the discovery of the Higgs Boston or the search for dark matter. But because the machines are so big, they’re very expensive and in limited quantity. Stanford University’s own accelerator is two miles long. But a new alternative discovered by researchers may change this. Researchers at Stanford have developed a laser-driven particle accelerator that fits on a silicon chip.
This smaller accelerator works in a similar fashion as a big one, albeit at a fraction of the velocity of the giant machine. This new version uses infrared lasers to deliver electrons much more quickly than the microwave radiation used in bigger accelerators. The team carved a nanoscale channel out of silicon, sealed it in a vacuum, and sent electrons through it while pulses of infrared light were transmitted by the channel walls to speed the electrons along. They used an inverse design approach, starting with algorithms that suggest the nanoscale structures that could allow for the right amounts of energy to be delivered in the right direction.
“The largest accelerators are like powerful telescopes. There are only a few in the world, and scientists must come to places like SLAC to use them,” electrical engineer and team leader Jelena Vuckovic said. “We want to miniaturize accelerator technology in a way that makes it a more accessible research tool.”
Right now, the accelerator chip is just a prototype and only provides one stage of acceleration. They would need roughly 1,000 stages to accelerate electrons to 94 percent the speed of light. But the team says this can be done since the prototype is a fully integrated circuit. All of the vital functions needed to accelerate particles are built into the chip. Researchers hope to pack the 1,000 necessary boosts into approximately an inch of the chip by the end of 2020.
The chip accelerator may not have the same power and versatility as its larger counterpart, it still could be useful in research and applications, particularly in the medical field. The team believes the method to create the chip could be scaled up to develop other devices capable of generating particle beams for experiments. It could also lead to new cancer radiation therapies. Olav Solgaard, a Stanford researcher, is currently working on an application of this chip that would guide the energized electrons through a catheter-like vacuum tube inserted alongside a tumor.
“We can derive medical benefits from the miniaturization of accelerator technology in addition to the research applications,” Solgaard stated.
Have a story tip? Message me at: cabe(at)element14(dot)com
