College of and Optical Engineering & College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications, Nanjing, 210023, China.
Phys Chem Chem Phys. 2023 Jul 5;25(26):17558-17570. doi: 10.1039/d3cp01944f.
The layered photonic structure (LPS) sensor presented in this paper utilizes the intrinsic absorption principle of graphene which can improve the absorption rate by stacking layers to generate an absorption peak within the terahertz (THz) frequency range. The absorption peak can be used for multi-dimensional detection of glucose solution, alcohol solution, the applied voltage of graphene, the thickness of hyperbolic metamaterials (HMs), and room temperature. LPS is endowed with characteristics of a Janus metastructure through the non-stacked arrangement of different media and can have different sensing properties when the electromagnetic waves (EWs) are incident forward and backward. The Janus metastructure features in the forward and backward direction make it have different physical characteristics, forming sensors with different resolutions and qualities, so as to realize the detection of multiple physical quantities. One device has the detection performance of multiple substances, which greatly improves the utilization rate of the design structure. Furthermore, the addition of HM to the sensor structure enables it to exhibit angle-insensitive characteristics in both forward and backward directions. To further enhance the sensor's performance, the particle swarm optimization (PSO) algorithm is used to optimize structural parameters. The resulting sensor exhibits excellent sensing performance, with a high sensitivity () of 940.34 THz per RIU and quality factor () and figure of merit (FOM) values of 37 4700 RIU, respectively, when measuring voltage. For glucose and alcohol solutions, the sensor demonstrates values of 5.52 THz per RIU and 4.44 THz per RIU, values of 8.3 and 37.2, and FOM values of 6.2 RIU and 20.2 RIU, respectively in different directions.
本文提出的分层光子结构（LPS）传感器利用了石墨烯的固有吸收原理，通过堆叠层可以提高吸收率，在太赫兹（THz）频率范围内产生吸收峰。该吸收峰可用于葡萄糖溶液、酒精溶液、石墨烯施加电压、双曲超材料（HMs）厚度和室温的多维检测。通过不同介质的非堆叠排列，LPS 被赋予了 Janus 亚结构的特性，当电磁波（EW）正向和反向入射时，它可以具有不同的传感特性。Janus 亚结构在正向和反向的特征使它具有不同的物理特性，形成具有不同分辨率和质量的传感器，从而实现对多个物理量的检测。一个器件具有多个物质的检测性能，大大提高了设计结构的利用率。此外，将 HM 添加到传感器结构中，可使传感器在正向和反向都具有角度不敏感的特性。为了进一步提高传感器的性能，采用粒子群优化（PSO）算法对结构参数进行优化。所得到的传感器具有出色的传感性能，当测量电压时，其灵敏度（）为 940.34 THz/RIU，品质因数（）和优值（FOM）分别为 374700 RIU 和 6.2 RIU。对于葡萄糖和酒精溶液，传感器在不同方向的 值分别为 5.52 THz/RIU 和 4.44 THz/RIU， 值分别为 8.3 和 37.2，FOM 值分别为 6.2 RIU 和 20.2 RIU。
