- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
[IEEE 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - Munich, Germany (2019.6.23-2019.6.27)] 2019 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC) - All-Dielectric High-Q Metasurfaces for Infrared Absorption Spectroscopy Applications
摘要： The mid-infrared (mid-IR) spectral range is crucial for spectroscopic investigations of biological systems since it contains the characteristic absorption signatures (i.e., the molecular ‘fingerprints’) of chemical and biological analytes, which are uniquely determined by the vibrational modes and associated absorption bands of its chemical bonds. Here we present a novel nanophotonics-based approach for detecting molecular fingerprints, which utilizes imaging-based methods to provide spectrometer-less operation in a miniaturized sensor device ideally suited for analyzing complex biological systems. The central building block of this technique is a pixelated dielectric metasurface where the individual metapixels are engineered to provide sharp resonances at a given resonance frequency. Each metapixel is made out of specifically designed zig-zag resonator arrays, which employ the concept of bound states in continuum to create high-Q resonances. The detection performance of the experimentally realized metasurface sensor was demonstrated by interrogating a monolayer of recombinant protein A/G molecules, which reveals the characteristic amide I and amide II absorption bands as distinct regions with attenuated peak reflectance of the resonances. A comparison of the total reflectance signals of all the metapixels before and after material adsorption delivers a distinct barcode pattern which can be used for chemically specific molecule detection. Importantly, this molecular barcoding method operates under broadband illumination and detection conditions, meaning that the chemically specific signals can be obtained without the need for spectrometry.
关键词： high-Q resonances,dielectric metasurface,nanophotonics,molecular barcoding,mid-infrared,molecular fingerprints
更新于2025-09-11 14:15:04
-
Meta-optics and bound states in the continuum
摘要： We discuss the recent advances in meta-optics and nanophotonics associated with the physics of bound states in the continuum (BICs). Such resonant states appear due to a strong coupling between leaky modes in optical guiding structures being supported by subwavelength high-index dielectric Mie-resonant nanoantennas or all-dielectric metasurfaces. First, we review brie?y very recent developments in the BIC physics in application to isolated subwavelength particles. We pay a special attention to novel opportunities for nonlinear nanophotonics due to the large ?eld enhancement inside the particle volume creating the resonant states with high-quality (high-Q) factors, the so-called quasi-BIC, that can be supported by the subwavelength particles. Second, we discuss novel applications of the BIC physics to all-dielectric optical metasurfaces with broken-symmetry meta-atoms when tuning to the BIC conditions allows to enhance substantially the Q factor of the ?at-optics dielectric structures. We also present the original results on nonlinear high-Q metasurfaces and predict that the frequency conversion ef?ciency can be boosted dramatically by smart engineering of the asymmetry parameter of dielectric metasurfaces in the vicinity of the quasi-BIC regime.
关键词： bound states in the continuum,high-Q resonances,nanophotonics,nonlinear nanophotonics,BICs,dielectric metasurfaces,meta-optics
更新于2025-09-09 09:28:46