High-quality multispectral bio-sensing with asymmetric all-dielectric meta-materials
High-quality multispectral bio-sensing with asymmetric all-dielectric meta-materials
复制标题
采用非对称全介电超材料的高质量多光谱生物传感
DOI：
10.1088/1361-6463/aa6384
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
Liu Guiqiang
中科院分区：
文献类型：
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作者：
Liu Zhengqi;Fu Guolan;Liu Xiaoshan;Liu Yi;Tang Li;Liu Zhongmin;Liu Guiqiang
我们提出并论证了一种在非对称全介质超材料中实现高质量生物传感的策略(α-ADM)，该策略可以为多光谱窄带光学消光提供增强的电磁场，并最终铺设一种新的高效传感平台。在该无损α-ADM平台上实现了比金属等离子体传感器高一个数量级的高性能光学传感，其优值系数达到353，光谱强度变化相关的FOM*超过4700。特别是，由于尖锐光谱的高灵敏度和完全消光，当周围的折射率值只有很小的变化时，就可以获得从暗状态到亮状态的显著的光谱强度变化。此外，可以实现对蛋白质层的超低检测极限，最小可达亚纳米厚度。对于吸附了蛋白质膜的传感器，传感器的传感对比度超过34dB，这表明该超薄生物分子层具有超高的信噪比检测能力。与传统的等离子体传感器相比，这些特点为基于全介质结构的新型传感方案奠定了基础。α-ADM的光谱灵敏度和探测信噪比等传感性能均能满足高质量折射率传感和光学生物传感的要求。
We propose and demonstrate a strategy for achieving high-quality bio-sensing in an asymmetric all-dielectric meta-material (α-ADM), which can provide multispectral narrowband optical extinction with enhanced electromagnetic field and eventually paves a novel efficient sensing platform. High performance optical sensing with figure of merit (FoM) reaching 353 and spectral intensity change related FoM* exceeding 4700 is achieved in this lossless α-ADM platform, which is orders of magnitude larger than that of the metallic plasmonic sensors. In particular, due to the high sensitivity and complete extinction existed in the sharp spectrum, a remarkable spectral intensity change from a'dark'state to a'bright'state is obtained when the surrounding refractive index value is only varied slightly. Moreover, ultra-low detection limitation of the protein layer down to sub-nanometer thickness can be achieved. The sensing contrast ratio exceeding 34 dB is obtained for the sensor adsorbed with protein films, which suggests an ultra-high signal-to-noise ratio detection for this ultra-thin bio-molecule layer. In contrast to the traditional plasmonic sensors, these features lay a foundation for new sensing schemes based on the all-dielectric structures. The sensing performance including the spectral sensitivity and the detecting signal-to-noise ratio can hold the proposed α-ADM with applications in high-quality refractive index sensing and optical bio-sensing.