A laser-driven electron accelerator that is integrated on a chip has been created by Jelena Vučković and colleagues at Stanford University. The device was developed using inverse design algorithms and comprises a highly complex silicon waveguide that is driven by near-infrared pulses. Soon, the researchers hope that the technology can be used to accelerate electrons to energies of about 1 MeV.
Conventional accelerators use radio-frequency (RF) radiation to boost charge particles to relativistic speeds. While incredibly useful in both science and medicine, such accelerators are large and expensive – putting them out of reach of many universities, research institutes and hospitals.
Dielectric laser accelerators (DLAs) offer a promising way of creating smaller and cheaper electron accelerators. They work by firing pulses of visible or near-infrared light onto nanostructures such as silicon pillars or gratings. The nanostructures are in an evacuated channel through which a beam of low-energy electrons is sent to be accelerated by the light. By using radiation at much shorter wavelengths, DLAs can be around 10,000 times smaller than conventional RF accelerators.To read more, click here.