Silicon metasurfaces with tunable electromagnetic resonances for nonlinear optical conversion
Year: 2021
Authors: Fagiani L.; Zilli A.; Tognazzi A.; Mafakheri E.; Okhlopkov K.; Rocco D.; Shcherbakov M.; Fedyanin A.; De Angelis C.; Finazzi M.; Celebrano M.; Bollani M.
Autors Affiliation: Politecn Milan, Dept Phys, Piazza L Da Vinci 32, I-20133 Milan, Italy; CNR IFN, LNESS Lab, Via Anzani 42, I-22100 Como, Italy; Univ Brescia, Dept Informat Engn, Via Branze 38, Brescia, Italy; CNR INO, Via Branze 45, I-25123 Brescia, Italy; Lomonosov Moscow State Univ, Fac Phys, Moscow 119991, Russia.
Abstract: Dielectric metasurfaces sustain electromagnetic modes which can be exploited to enhance nonlinear frequency-conversion processes such as third-harmonic generation. In this work we employ electron-beam lithography to fabricate silicon metasurfaces supporting electromagnetic resonances with different quality factors (Q), ruled by the geometry. This allows to investigate the trade-off between resonant enhancement and matching the spectral bandwidth of the ultrafast excitation source. Both experiments and simulations indicate that higher values of Q do not a priori bring about a stronger third-harmonic generation, which correlates to the spectral overlap between the metasurface resonance and the pump bandwidth.
Journal/Review: Nuovo Cimento C-Colloquia and Communications in Physics
Volume: 44 (05-May) Pages from: 111-1 to: 111-4
KeyWords: Dielectric metasurfaces, nonlinear frequency-conversion, SOI, third-harmonic generationDOI: 10.1393/ncc/i2021-21111-9
