Metasurfaces for molecular detection Although mid-infrared (mid-IR) spectroscopy is a mainstay of molecular fingerprinting, its sensitivity is diminished somewhat when looking at small volumes of sample. Nanophotonics provides a platform to enhance the detection capability. Tittl et al. built a mid-IR nanophotonic sensor based on reflection from an all-dielectric metasurface array of specially designed scattering elements. The scattering elements could be tuned via geometry across a broad range of wavelengths in the mid-IR. The approach successfully detected and differentiated the absorption fingerprints of various molecules. The technique offers the prospect of on-chip molecular fingerprinting without the need for spectrometry, frequency scanning, or moving mechanical parts. Science, this issue p. 1105 A pixelated dielectric metasurface is used for the mid-infrared detection of molecular fingerprints. Metasurfaces provide opportunities for wavefront control, flat optics, and subwavelength light focusing. We developed an imaging-based nanophotonic method for detecting mid-infrared molecular fingerprints and implemented it for the chemical identification and compositional analysis of surface-bound analytes. Our technique features a two-dimensional pixelated dielectric metasurface with a range of ultrasharp resonances, each tuned to a discrete frequency; this enables molecular absorption signatures to be read out at multiple spectral points, and the resulting information is then translated into a barcode-like spatial absorption map for imaging. The signatures of biological, polymer, and pesticide molecules can be detected with high sensitivity, covering applications such as biosensing and environmental monitoring. Our chemically specific technique can resolve absorption fingerprints without the need for spectrometry, frequency scanning, or moving mechanical parts, thereby paving the way toward sensitive and versatile miniaturized mid-infrared spectroscopy devices.

中文翻译：

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具有像素化介电超表面的基于成像的分子条形码

用于分子检测的超表面 尽管中红外 (mid-IR) 光谱是分子指纹识别的支柱，但在观察小体积样品时其灵敏度会有所降低。纳米光子学提供了一个增强检测能力的平台。蒂特尔等人。基于来自特殊设计的散射元件的全介电超表面阵列的反射，构建了一个中红外纳米光子传感器。散射元件可以通过几何形状在中红外的广泛波长范围内进行调整。该方法成功地检测并区分了各种分子的吸收指纹。该技术提供了片上分子指纹识别的前景，而无需光谱、频率扫描或移动机械部件。科学，这个问题 p。1105 像素化介电超表面用于分子指纹的中红外检测。超表面为波前控制、平面光学和亚波长光聚焦提供了机会。我们开发了一种基于成像的纳米光子方法来检测中红外分子指纹，并将其用于表面结合分析物的化学鉴定和成分分析。我们的技术具有二维像素化介电超表面，具有一系列超锐共振，每个共振都调谐到离散频率；这使得能够在多个光谱点读取分子吸收特征，然后将所得信息转换成类似条形码的空间吸收图进行成像。生物、聚合物、可以高灵敏度检测农药分子，涵盖生物传感和环境监测等应用。我们的化学特异性技术无需光谱测定、频率扫描或移动机械部件即可解析吸收指纹，从而为实现灵敏且多功能的小型化中红外光谱设备铺平道路。