Haeusler U, Seidling M, Yousefi P, Hommelhoff P (2022)
Publication Type: Journal article
Publication year: 2022
DOI: 10.1021/acsphotonics.1c01687
The generation of radiation from free electrons passing a grating, known as Smith-Purcell radiation, finds various applications, including nondestructive beam diagnostics and tunable light sources, ranging from terahertz toward X-rays. So far, the gratings used for this purpose have been designed manually, based on human intuition and simple geometric shapes. Here we apply the computer-based technique of nanophotonic inverse design to build a 1400 nm Smith-Purcell radiator for subrelativistic 30 keV electrons. We demonstrate that the resulting silicon nanostructure radiates with a 3X higher efficiency and 2.2X higher overall power than previously used rectangular gratings. With better fabrication accuracy and for the same electron-structure distance, simulations suggest a superiority by a factor of 96 in peak efficiency. While increasing the efficiency is a key step needed for practical applications of free-electron radiators, inverse design also allows to shape the spectral and spatial emission in ways inaccessible with the human mind.
APA:
Haeusler, U., Seidling, M., Yousefi, P., & Hommelhoff, P. (2022). Boosting the Efficiency of Smith-Purcell Radiators Using Nanophotonic Inverse Design. ACS Photonics. https://dx.doi.org/10.1021/acsphotonics.1c01687
MLA:
Haeusler, Urs, et al. "Boosting the Efficiency of Smith-Purcell Radiators Using Nanophotonic Inverse Design." ACS Photonics (2022).
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