等离激元晶体型双曲超材料生物传感器新机理及关键工艺研究

In the optical biosensor technology, the demand for higher sensitivity and larger quality factor has become a common understanding in the scientific community, in which the hyperbolic metamaterial biosensor has attracted much attention because of its novel working principle and excellent performance. This project introduces the slow-light effect into biosensor technology based on metal nanorod hyperbolic metamaterials, and proposes a new mechanism of slow-light effect which can significantly improve the sensing sensitivity. This project also presents the grating coupler composed of the periodic structure of the plasmon polaritonic crystal type combined with the metal nanorod hyperbolic metamaterial waveguide to excite the TM guided mode with slow light effect in the critical condition of the metamaterial waveguide, in which the High quality factor integrated biochip can be obtained. In this project, we study the dispersion properties of metal nanorod hyperbolic metamaterial waveguide, the physical mechanism of slow light effect. The effects of critical conditions and loss factors on the slow-light effect are also investigated. An integrated nano biosensor sample with slow light enhancement effect is explored and fabricated by using the semiconductor process. The implementation of this project will show a new direction for the development of cross-fusion of metamaterials, micro-nano integration and optical biosensor. At the same time, the slow light effect of hyperbolic metamaterials also has a bright future in optical non-linear devices, optical buffers, optical routers and so on.

在光学生物传感技术中，进一步提高传感灵敏度、增大品质因子的需求已被科学界达成共识。而双曲线型超材料生物传感器因其新颖的工作原理和优异的性能更是成为备受关注的科学热点。本项目创新性地将慢光效应引入金属纳米柱双曲线型超材料生物传感技术中，提出慢光效应能显著提高传感灵敏度的物理新机理，并提出将等离激元晶体型周期结构的光栅耦合器与金属纳米柱双曲线型超材料波导合二为一，激发出在超材料波导临界条件下具有慢光效应的TM导模，可获得高品质因子的集成生物芯片。本项目研究金属纳米柱双曲线型超材料波导色散性质；慢光效应的物理机理；临界条件和损耗因素对慢光效应的影响；利用半导体工艺探索制作具有慢光增强效应的可集成的微纳生物传感器样品。该项目的实施将会对超材料、微纳集成和光学生物传感交叉融合展示了一个新的发展方向。同时，双曲线型超材料的慢光效应在光学非线性器件，光缓存、光路由器等一系列方面展现了良好的研究前景。

在健康产业的药物和食品安全等领域中, 长期服用抗生素类药物会导致自身免疫降低引发内源性感染，危害人体健康。建立检测抗生素有效的方法十分重要。在生物医学早期诊断方面，光学生物传感器由于其抗干扰能力强、非接触和非破坏性测量，特别是其中基于等离激元双曲线型超材料的生物传感器具有对环境折射率变化极为敏感的特殊优势，有着极其重要的应用价值和宽广的发展前景。. 针对双曲线型超材料的生物传感器，我们提出了一种基于循环神经网络的深度学习方法来提取光谱的序列特征并实现逆向设计和光谱预测。该模型验证了目标光谱和模型预测的光谱之间的高度一致性，模型学习了光谱与结构参数的深层物理关系。也使用自定义的高斯光谱对反向设计模型的有效性进行了验证。.我们同时研究了多种结构金属裂口环共振器的表面等离激元超材料折射率传感器件。研究的结构中支持等离激元奇模式和偶模式共振，环境折射率的改变导致奇模式和偶模式共振波长明显的红移，传感灵敏度为1000 nm/RIU，还具有偏振无依赖性的特点。. 对双曲超材料生物传感器慢光机理及关键工艺进行了深入研究。建立了这种全新机理的生物传感理论模型，我们利用lift-off工艺探索研制了超高灵敏度的生物传感器实验样品。采用EBL纳米级精度图形的光刻，电化学生长沉积，制备出排列均匀整齐的金纳米柱双曲线型超材料的芯片。利用搭建的光谱测试系统测试了生物传感器。在近红外波段传感器测试了甘油溶液，其折射率体灵敏度41600 nm/RIU，反射谱线的带宽为100 nm，得到品质因子FOM为416/RIU。测试结果超过基金项目制定的传感器灵敏度30000 nm/RIU目标。