Although the acceleration, demonstrated as an extra 0.915 keV gained along a 30µm-long channel, is only a fraction of what’s achievable with giant particle accelerators such as the 2 miles long instrument at Stanford’s SLAC National Accelerator Laboratory, it is designed at a scale several orders of magnitude smaller. Hence, the researchers anticipate that hundreds or even thousands of such silicon-based particle accelerators, only a few micrometers in size, could be operated in cascade to accelerate particles in useful high-energy beams.
The researchers carved a nanoscale channel out of silicon only 30µm-long, sealed it in a vacuum and sent electrons through this cavity while pulses of infrared light - to which silicon is transparent - were transmitted by the channel walls to speed the electrons along. The accelerator-on-a-chip demonstrated in Science is just a prototype, but the design and fabrication techniques used are easily scalable and in the future, small portable accelerators could deliver particle beams accelerated enough to perform cutting-edge experiments in chemistry, materials science and biological discovery that don't require the power of a massive accelerator.
"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," explains Jelena Vuckovic, electrical engineer at Stanford and team leader on this research. "We want to miniaturize accelerator technology in a way that makes it a more accessible research tool."