An anonymous reader quotes a report from TechCrunch: “We want to miniaturize accelerator technology in a way that makes it a more accessible research tool,” explained project lead Jelena Vuckovic in a Stanford news release. But this wasn’t designed like a traditional particle accelerator like the Large Hadron Collider or one at collaborator SLAC’s National Accelerator Laboratory. Instead of engineering it from the bottom up, they fed their requirements to an “inverse design algorithm” that produced the kind of energy pattern they needed from the infrared radiation emitters they wanted to use. That’s partly because infrared radiation has a much shorter wavelength than something like microwaves, meaning the mechanisms themselves can be made much smaller — perhaps too small to adequately design the ordinary way. The algorithm’s solution to the team’s requirements led to an unusual structure that looks more like a Rorschach test than a particle accelerator. But these blobs and channels are precisely contoured to guide infrared laser light pulse in such a way that they push electrons along the center up to a significant proportion of the speed of light.
The resulting “accelerator on a chip” is only a few dozen microns across, making it comfortably smaller than a human hair and more than possible to stack a few on the head of a pin. A couple thousand of them, really. And it will take a couple thousand to get the electrons up to the energy levels needed to be useful — but don’t worry, that’s all part of the plan. The chips are fully integrated but can be put in a series easily to create longer assemblies that produce larger powers. These won’t be rivaling macro-size accelerators like SLAC’s or the Large Hadron Collider, but they could be much more useful for research and clinical applications where planet-destroying power levels aren’t required. For instance, a chip-sized electron accelerator might be able to direct radiation into a tumor surgically rather than through the skin. The findings have been published in the journal Science.