Ultrafast all-optical modulation of wide-bandwidth pulses enabled by silicon-metasurfaces
硅超表面实现宽带脉冲的超快全光调制
シリコン超表面による広帯域パルスの超高速全光変調を実現
실리콘 메타 표면에 의해 가능한 광범위 실실리폭 실실실리콘 메타 표면에 의해 가능한 초빠른 광학적 모듈레이션
Modulación óptica ultrarápida de pulsos de ancho de banda amplio habilitada por metasuperficies de silicio
Modulation tout optique ultrarapide d'impulsions à large bande passante grâce aux métasurfaces de silicium
Ультрабыстрая полнооптическая модуляция импульсов широкополосной пропускной способности, обеспечиваемая кремниевыми метаповерхностями
Kaloyan Georgiev ¹ ², Khosro Zangeneh Kamali ³ ⁴, Anton A. Trifonov ², Giulia Crotti ⁵, Lyuben Petrov ¹ ², Stefan Georgiev ¹, Hristo Iliev ¹, Lei Xu ⁶, Unai Arregui Leon ⁵, Mohsen Rahmani ⁶, Giuseppe Della Valle ⁵, Ivan Buchvarov ¹ ² ⁷, Dragomir Neshev ² ³
¹ Department of Physics, Sofia University St. Kliment Ohridski, Sofia 1164, Bulgaria
² John Atanasoff Center for Bio and Nano Photonics (JAC BNP), Sofia 1164, Bulgaria
³ ARC Centre of Excellence for Transformative Meta-Optical Systems (TMOS), Dept. of Electronic Materials Engineering, Research School of Physics, Australian National University, ACT 2601, Australia
⁴ Department of Physics, Chalmers University of Technology, Gothenburg 412 96, Sweden
⁵ Dipartimento di Fisica - Politecnico di Milano, Milano 20133, Italy
⁶ Advanced Optics and Photonics Laboratory, Department of Engineering, School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, United Kingdom
⁷ Institute of Solid State Physics, Bulgarian Academy of Sciences, Tsarigradsko Chaussee 72, Sofia 1784, Bulgaria
Semiconductor metasurfaces have emerged as an effective platform for all-optical modulation thanks to their resonant light confinement and the enhancement of ultrafast optical effects like the Kerr effect and free-carrier generation. However, their narrow resonance features also restrict the available bandwidth for efficient modulation. Here, we demonstrate that a kink-like transmission spectral profile of a silicon metasurface could enable high-contrast modulation of wide-bandwidth pulses.
We studied the all-optical ultrafast transmission modulation of the silicon metasurface induced by free-carrier excitation in a pump-probe configuration at different polarizations. We achieved ultrafast modulation of 28% (10%) with a speed of 25 ps and a bandwidth of up to 14 nm (49 nm) for y- and x-polarizations, respectively. Our results open up new opportunities for high-contrast, all-optical modulation of short pulses, with applications in optical communications and computing.
