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arXiv · 1905.12822

On-chip integrated laser-driven particle accelerator

Neil V. Sapra·Ki Youl Yang·Dries Vercruysse·Kenneth J. Leedle·Dylan S. Black·R. Joel England·Logan Su·Yu Miao·Olav Solgaard·Robert L. Byer·Jelena Vučković
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Abstract

Particle accelerators represent an indispensable tool in science and industry. However, the size and cost of conventional radio-frequency accelerators limit the utility and reach of this technology. Dielectric laser accelerators (DLAs) provide a compact and cost-effective solution to this problem by driving accelerator nanostructures with visible or near-infrared (NIR) pulsed lasers, resulting in a 10$^4$ reduction of scale. Current implementations of DLAs rely on free-space lasers directly incident on the accelerating structures, limiting the scalability and integrability of this technology. Here we present the first experimental demonstration of a waveguide-integrated DLA, designed using a photonic inverse design approach. These on-chip devices accelerate sub-relativistic electrons of initial energy 83.4 keV by 1.21 keV over 30 um, providing peak acceleration gradients of 40.3 MeV/m. This progress represents a significant step towards a completely integrated MeV-scale dielectric laser accelerator.

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Neil V. Sapra, Ki Youl Yang, Dries Vercruysse, Kenneth J. Leedle, Dylan S. Black, R. Joel England, Logan Su, Yu Miao, Olav Solgaard, Robert L. Byer, Jelena Vučković. 2019-05-30. On-chip integrated laser-driven particle accelerator. https://doi.org/10.1126/science.aay5734

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