二维声光子晶体异质结构腔的传感性能  

Sensing Performance of Two-Dimensional Phoxonic Crystal Heterostructure Cavity

作　　者：王旭 田苗[1] 马振猛 张磊[1] Wang Xu;Tian Miao;Ma Zhenmeng;Zhang Lei(School of Mathematics and Physics,Lanzhou Jiaotong University,Lanzhou 730070,Gansu,China)

机构地区：[1]兰州交通大学数理学院,甘肃兰州730070

出　　处：《光学学报》2024年第14期288-298,共11页Acta Optica Sinica

基　　金：甘肃省高等学校产业支撑项目(2022CYZC-06);兰州交通大学-天津大学联合创新基金(2021057)。

摘　　要：采用有限元法(FEM)进行数值模拟,首先设计了一种二维声光子晶体异质结构腔传感结构,该结构可以有效地将特定频率的声子和光子能量限制在腔内;然后,在腔内注入不同液体,计算了不同腔模式的声光传感参量。研究结果表明,该传感结构的最高声学和光学灵敏度分别达到了3.289 MHz/(m·s^(-1))和825 nm/RIU。在声学传感方面,该结构存在双特征峰,从而提高了声学传感的稳定性和准确性。该结构同时实现了声场和光场的局域,提高了声光信号的传感灵敏度,为液体多物理量传感提供了新的思路。Objective In recent years, the structural design and application of phoxonic crystals have received extensive attention. Its main feature is the simultaneous manipulation and modulation of acoustic waves and optical waves, receiving the localization of photons and phonons in the same structure. Traditional phononic or photonic crystal sensors detect the acoustic or optical properties of the object under test in a single channel, while the phoxonic crystal sensor can sense the optical signal and the acoustic signal at the same time, realize the acousto-optic dual-channel detection of the object to be measured and improve the sensing accuracy of the object under test to a certain extent. In this study, we design a phoxonic crystal sensor with a heterogeneous cavity that can simultaneously measure the refractive index and sound velocity of the liquid and achieved high sensitivity sensing for three types of liquids. Therefore, it can be applied to the field of measurement of related physical quantities of liquids and may have application value in biochemical sensing and water quality monitoring, etc.Methods Our main calculation method is the finite element method, which is combined with COMSOL Multiphysics 6.0 software. Firstly, the designed structural model is discretized into a certain number of finite small element ensembles.According to the elastic wave propagation equation or Maxwell's equation of electromagnetic waves, the relationship between the element junction force and the node displacement is created by combining the variational principle, and then the finite element equation is established according to the equilibrium condition of the junction force. Boundary conditions are introduced at the structure boundary and the system of linear equations is solved to obtain the band structures of phonon and photons. To calculate the light transmittance, we apply the scattering boundary condition to all the outer boundaries of the structure, setting port 1 at the left boundary of the air slit region to apply excita

关 键 词：物理光学 声光子晶体 声光子带隙 异质结构腔 声光传感 灵敏度 

分 类 号：O436[机械工程—光学工程]