Inverse-Designed Narrowband THz Radiator for Ultrarelativistic Electrons

Hermann B, Häusler U, Yadav G, Kirchner A, Feurer T, Welsch C, Hommelhoff P, Ischebeck R (2022)

Publication Language: English

Publication Type: Journal article

Publication year: 2022



DOI: 10.1021/acsphotonics.1c01932


THz radiation finds various applications in science and technology. Pump–probe experiments at free-electron lasers typically rely on THz radiation generated by optical rectification of ultrafast laser pulses in electro-optic crystals. A compact and cost-efficient alternative is offered by the Smith–Purcell effect: a charged particle beam passes a periodic structure and generates synchronous radiation. Here, we employ the technique of photonic inverse design to optimize a structure for Smith–Purcell radiation at a single wavelength from ultrarelativistic electrons. The resulting design is highly resonant and emits narrowbandly. Experiments with a 3D-printed model for a wavelength of 900 μm show coherent enhancement. The versatility of inverse design offers a simple adaption of the structure to other electron energies or radiation wavelengths. This approach could advance beam-based THz generation for a wide range of applications.

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Hermann, B., Häusler, U., Yadav, G., Kirchner, A., Feurer, T., Welsch, C.,... Ischebeck, R. (2022). Inverse-Designed Narrowband THz Radiator for Ultrarelativistic Electrons. ACS Photonics.


Hermann, Benedikt, et al. "Inverse-Designed Narrowband THz Radiator for Ultrarelativistic Electrons." ACS Photonics (2022).

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