Benea-Chelmus Ileana-Cristina, Mason Sydney, Meretska Maryna L, Elder Delwin L, Kazakov Dmitry, Shams-Ansari Amirhassan, Dalton Larry R, Capasso Federico
Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
Hybrid Photonics Laboratory, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Nat Commun. 2022 Jun 6;13(1):3170. doi: 10.1038/s41467-022-30451-z.
Electro-optic modulators are essential for sensing, metrology and telecommunications. Most target fiber applications. Instead, metasurface-based architectures that modulate free-space light at gigahertz (GHz) speeds can boost flat optics technology by microwave electronics for active optics, diffractive computing or optoelectronic control. Current realizations are bulky or have low modulation efficiencies. Here, we demonstrate a hybrid silicon-organic metasurface platform that leverages Mie resonances for efficient electro-optic modulation at GHz speeds. We exploit quasi bound states in the continuum (BIC) that provide narrow linewidth (Q = 550 at [Formula: see text] nm), light confinement to the non-linear material, tunability by design and voltage and GHz-speed electrodes. Key to the achieved modulation of [Formula: see text] are molecules with r = 100 pm/V and optical field optimization for low-loss. We demonstrate DC tuning of the resonant frequency of quasi-BIC by [Formula: see text] 11 nm, surpassing its linewidth, and modulation up to 5 GHz (f = 3 GHz). Guided mode resonances tune by [Formula: see text] 20 nm. Our hybrid platform may incorporate free-space nanostructures of any geometry or material, by application of the active layer post-fabrication.
电光调制器对于传感、计量学和电信至关重要。大多数针对光纤应用。相反，基于超表面的架构能够以吉赫兹（GHz）速度调制自由空间光，可通过微波电子学推动平面光学技术用于有源光学、衍射计算或光电控制。目前的实现方式体积庞大或调制效率较低。在此，我们展示了一种混合硅有机超表面平台，该平台利用米氏共振在GHz速度下实现高效电光调制。我们利用连续谱中的准束缚态（BIC），其提供窄线宽（在[公式：见正文] nm处Q = 550）、将光限制在非线性材料中、通过设计和电压以及GHz速度电极实现可调谐性。实现[公式：见正文]调制的关键在于r = 100 pm/V的分子以及用于低损耗的光场优化。我们展示了准BIC共振频率的直流调谐范围达[公式：见正文] 11 nm，超过其线宽，以及高达5 GHz（f = 3 GHz）的调制。导模共振调谐范围达[公式：见正文] 20 nm。通过在制造后应用有源层，我们的混合平台可以纳入任何几何形状或材料的自由空间纳米结构。
