Silicon metasurfaces with tunable electromagnetic resonances for nonlinear optical conversion
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: Department of Physics, Politecnico di Milano -, Piazza L. Da Vinci 32, Milano, 20133, Department of Physics, Politecnico di Milano – Piazza L. Da Vinci 32, 20133 Milano, Italy, , Italy; CNR-IFN, LNESS laboratory, Via Anzani 42, Como, 22100, CNR-IFN, LNESS laboratory – Via Anzani 42, 22100 Como, Italy, , Italy; Department of Information Engineering, University of Brescia, Via Branze 38, Brescia, Department of Information Engineering, University of Brescia – Via Branze 38, Brescia, Italy, , Italy; CNR-INO -, Via Branze 45, Brescia, 25123, CNR-INO – Via Branze 45, 25123 Brescia, Italy, , Italy; Faculty of Physics, Lomonosov Moscow State University, Moscow, 119991, Faculty of Physics, Lomonosov Moscow State University – Moscow 119991, Russia, , Russian Federation
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: IL NUOVO CIMENTO C (ONLINE)
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