Dolia Varun, Balch Halleh B, Dagli Sahil, Abdollahramezani Sajjad, Carr Delgado Hamish, Moradifar Parivash, Chang Kai, Stiber Ariel, Safir Fareeha, Lawrence Mark, Hu Jack, Dionne Jennifer A
Department of Materials Science and Engineering, Stanford University, Stanford, CA, USA.
Department of Electrical Engineering, Stanford University, Stanford, CA, USA.
Nat Nanotechnol. 2024 Sep;19(9):1290-1298. doi: 10.1038/s41565-024-01697-z. Epub 2024 Jul 3.
Metasurfaces precisely control the amplitude, polarization and phase of light, with applications spanning imaging, sensing, modulation and computing. Three crucial performance metrics of metasurfaces and their constituent resonators are the quality factor (Q factor), mode volume (V) and ability to control far-field radiation. Often, resonators face a trade-off between these parameters: a reduction in V leads to an equivalent reduction in Q, albeit with more control over radiation. Here we demonstrate that this perceived compromise is not inevitable: high quality factor, subwavelength V and controlled dipole-like radiation can be achieved simultaneously. We design high quality factor, very-large-scale-integrated silicon nanoantenna pixels (VINPix) that combine guided mode resonance waveguides with photonic crystal cavities. With optimized nanoantennas, we achieve Q factors exceeding 1,500 with V less than 0.1 . Each nanoantenna is individually addressable by free-space light and exhibits dipole-like scattering to the far-field. Resonator densities exceeding a million nanoantennas per cm can be achieved. As a proof-of-concept application, we show spectrometer-free, spatially localized, refractive-index sensing, and fabrication of an 8 mm × 8 mm VINPix array. Our platform provides a foundation for compact, densely multiplexed devices such as spatial light modulators, computational spectrometers and in situ environmental sensors.
超表面可精确控制光的幅度、偏振和相位,其应用涵盖成像、传感、调制和计算等领域。超表面及其组成谐振器的三个关键性能指标是品质因数(Q 因子)、模式体积(V)和控制远场辐射的能力。通常,谐振器在这些参数之间面临权衡:V 的减小会导致 Q 等效减小,尽管对辐射的控制更强。在此,我们证明这种看似的折衷并非不可避免:可以同时实现高品质因数、亚波长 V 和可控的偶极子状辐射。我们设计了将导模共振波导与光子晶体腔相结合的高品质因数、超大规模集成硅纳米天线像素(VINPix)。通过优化的纳米天线,我们实现了品质因数超过 1500 且 V 小于 0.1 。每个纳米天线均可通过自由空间光单独寻址,并向远场呈现偶极子状散射。可以实现每平方厘米超过一百万个纳米天线的谐振器密度。作为概念验证应用,我们展示了无需光谱仪的空间局部折射率传感以及 8 毫米×8 毫米 VINPix 阵列的制造。我们的平台为诸如空间光调制器、计算光谱仪和原位环境传感器等紧凑型、密集复用设备奠定了基础。