基于宇称-时间对称光子晶体结构的磁场传感器研究  

Research on magnetic field sensor based on parity-time symmetry photonic crystal structure

作　　者：易凌俊 李长红[1] YI Lingjun;LI Changhong(College of Electronic Information,Qingdao University,Qingdao,Shandong 266071,China)

机构地区：[1]青岛大学电子信息学院,山东青岛266071

出　　处：《光电子．激光》2022年第3期256-263,共8页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(61307050,61701271);山东省自然科学基金(ZR2016AM27)资助项目。

摘　　要：提出了一种基于宇称-时间(parity-time,PT)对称结构的磁场检测微腔模型,利用水基Fe_(3)O_(4)磁流体介质层的磁光效应和PT对称结构的光放大效应,当磁场强度发生变化时,引起结构禁带中缺陷模位置的改变。因此,可以通过检测缺陷模位置实现磁场强度的检测。本文利用传递矩阵法(transfer matrix method,TMM)从理论上分析了结构的透射光谱,在此基础上对结构周期、介质层厚度、PT对称单元中宏观洛伦兹振荡强度等参数进行了数值优化。优化后的仿真结果表明,该传感器能够实现有效的磁场磁强检测,磁场强度在0—500Oe的范围内,传感器的灵敏度可以达到97.14nm/RIU,优值和检测极限分别可以达到10^(4)和10^(-7) RIU。同时,传感器的分辨率数值最小可以达到0.05Oe和最大可以达到2Oe。本文所设计的传感器结构可用于高综合性能磁场强度检测设备的设计。A magnetic field detection micro-cavity model based on parity-time(PT)symmetry structure is proposed.Using the magnetic-optical effect of hydro-based Fe_(3)O_(4) magnetic fluid medium layer and the optical amplification effect of the PT-symmetry structure,when the magnetic field strength changes,the defect mode position in the structure band gap is changed.Therefore,the magnetic field intensity can be detected by detecting the defect mode position.In this paper,the transmission spectrum of the structure is theoretically analyzed based on the transfer matrix method(TMM),and the parameters such as the structure period,the thickness of the dielectric layer and the macroscopic Lorentz oscillation intensity in the PT-symmetry element are numerically optimized.The optimized simulation results show that the sensor can achieve effective magnetic field intensity detection,the sensitivity of the sensor can reach 97.14nm/RIU in the magnetic field intensity range of 0—500Oe,the figure of merit and detection limit can reach 10^(4) and 10^(-7) RIU,respectively.Meanwhile,the resolution value can be as low as 0.05Oe and as high as 2Oe.The proposed sensor structure can be used in the design of high comprehensive performance magnetic field intensity testing equipment.

关 键 词：宇称-时间(parity-time PT)对称 磁光效应 传递矩阵(transfer matrix method TMM) 磁场传感器 

分 类 号：O431.1[机械工程—光学工程] TP212[理学—光学]