A novel plasmonic device: Filtering and switching functions with quasi-rectangular spectrum based on dual Fano resonances. (January 2023)

• Record Type: Journal Article
• Authors: Chai, Junxiong; Xie, Yiyuan; Zhang, Liangyi; Ye, Yichen; Liu, Bocheng; Jiang, Xiao; Yang, Rong; Tan, Jing
• Is Part Of: Optics & laser technology. Volume 157(2023)
• Publication Date: 2023-01
• Subjects: Integrated optics -- Signal processing -- Multifunctional device -- Surface plasmon polaritons -- Fano resonance; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2022.108692
• Languages: English
• ISSNs: 0030-3992

Abstract

Abstract: Compact filters and switches are essential building blocks for performing interference-mitigation and signal-selection in photonic integrated loop. A plasmonic device that exhibits multifunctions including filter and switch is proposed in this paper. The device consists of a hexagonal resonator with rotatable oval core, a stub and two tooth cavities coupled with bus waveguide, respectively. The temporal coupled-mode theory reveals that dual Fano resonances occur in the structure. Finite-difference time-domain method indicates that the bandwidth and transmission of the spectrum can be manipulated by adjusting the parameters of elliptical rotor and stub cavity. Passband ripple is calculated under different structural parameters, and spectrum with low passband ripple of 0.023 dB is realized. Moreover, rotation of the elliptical rotor in the hexagonal resonator will alter transmission spectrum of the output port. Ultimately, filtering and switching functions with quasi-rectangular spectrum are implemented in the designed structure, which will enhance device performance and reduce signal distortion. The fabrication tolerance is analyzed considering widths of stub and tooth cavities. Furthermore, the selectivity of working wavelength at different channels is researched and presented. This novel plasmonic device with low passband ripple has a great impact on improving the quality of signals on chips. Highlights: An integrated multifunction device based on dual Fano resonances is designed. Filtering and switching functions with quasi-rectangular spectrum are implemented in the presented device. The quasi-rectangular spectrum improves the performance of device. The selectivity of working wavelength in commonly employed bands is discussed. The proposed device has a great impact on improving the quality of signals on chips.