Metasurfaces have unlocked significant advancements across photonics, yet their efficient active control remains challenging. The active materials required often lack continuous tunability, exhibit inadequate refractive index (RI) changes, or suffer from high losses. These aspects pose an inherent limitation for resonance-shifting based switching: when RI changes are small, the resulting shift is also minor. Conversely, high RI changes typically come with high intrinsic losses necessitating broad modes because narrow ones cannot tolerate such losses. Therefore, larger spectral shifts are required to effectively detune the modes. This paper introduces a novel active metasurface approach that converts the constraint of high intrinsic losses into a beneficial feature. This is achieved by controlling the losses in a hybrid vanadium dioxide (VO$_{2}$) - silicon metasurface, supporting symmetry-protected bound states in the continuum (BICs) within the infrared spectrum. By leveraging the temperature-controlled losses in VO$_{2}$ and combining them with the inherent far-field-coupling tunability of BICs, we gain unprecedented precision in independently controlling both the radiative and nonradiative losses of the resonant system. Our dual-control mechanism allows us to optimize our metasurfaces and we experimentally demonstrate quality factors above 200, a maximum reflectance amplitude of 90%, a relative switching contrast of 78%, and continuous tuning from under- to over-coupling within the infrared spectral range. This study provides a foundation for experimentally and technologically simple, fine-tunable, active metasurfaces for applications ranging from molecular sensors to filters and optical modulators.
Design of on-chip plasmonic modulator with vanadium-dioxide in hybrid orthogonal junctions on Silicon-on-Insulator
我们提出了一种基于混合正交银结的等离子体激元调制器，使用二氧化钒作为绝缘体上硅上的调制材料。该调制器具有1.8μm x 1μm的超紧凑尺寸，具有基于正交几何结构的100 nm x 100 nm调制部分。我们利用二氧化钒在相变过程中折射率发生较大变化的特点，实现了46.89dB/μm的高调制深度。我们还提供了一个制造策略，为该器件的发展。该器件的几何结构在下一代光通信高频光子调制器的开发中具有潜在的应用，该光通信高频光子调制器需要纳米尺度的足迹、大的调制深度和小的插入损耗。
Thermally switchable polarization manipulation and diodelike transmission in scalable, resonator-free, mid-infrared metasurfaces with vanadium-dioxide grids
Tuning of Localized Surface Plasmons in Vanadium Dioxide Nanoparticles via Size and Insulator-Metal Transition
Brno University of Technology（布尔诺理工大学）；Central European Institute of Technology（中欧技术研究所）；Center for Nanophase Materials Sciences, Oak Ridge National Laboratory（橡树岭国家实验室纳米材料科学中心）
Dynamically Babinet-invertible metasurface: a capacitive-inductive reconfigurable filter for terahertz waves using vanadium-dioxide metal-insulator transition
Sub-milliwatt threshold power and tunable-bias all-optical nonlinear activation function using vanadium dioxide for wavelength-division multiplexing photonic neural networks
Thermodynamics of the ultrafast phase transition of vanadium dioxide
IMDEA Nanoscience（IMDEA纳米科学研究所）；CNRS, Univ Rennes, Institut de Physique de Rennes（法国国家科学研究中心，雷恩大学，雷恩物理研究所）；The University of Tokyo（东京大学）；Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST（加泰罗尼亚纳米科学与技术研究所（ICN2），西班牙高等科学研究理事会和巴塞罗那综合理工学院）；Department of Physics and Astronomy, Aarhus University（奥胡斯大学物理与天文系）
