Open AccessFano-resonance-based Mach-Zehnder optical switch employing dual-bus coupled ring resonator as two-beam interferometer
Author(s) -
Fan Wang,
Xiang Wang,
Haifeng Zhou,
Qiang Zhou,
Yue Hao,
Xiaoqing Jiang,
Minghua Wang,
Jianyi Yang
Publication year - 2009
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.007708
Subject(s) - fano resonance , optics , interferometry , mach–zehnder interferometer , free spectral range , resonator , extinction ratio , optical switch , physics , coupled mode theory , refractive index , wavelength , plasmon
A kind of Mach-Zehnder optical switch with a dual-bus coupled ring resonator as a two-beam interferometer is proposed and investigated. The analysis based on the transfer matrix method shows that a sharp asymmetric Fano line shape can be generated in the transmission spectra of such a configuration, which can be used to significantly reduce the phase change required for switching. Meanwhile, it can also be found that complete extinctions can be achieved in both switching states if the structural parameters are carefully chosen and the phase bias is properly set. Through tuning the phase difference between the arms of the Mach-Zehnder interferometer, complete extinction can be easily kept within a large range of the ring-bus coupling ratios in the OFF state. By properly modulating the phase change in the ring waveguide, the shift of the resonant frequency and the asymmetry of the transmission spectra can be controlled to finally enable optical switching with a high extinction ratio, even complete extinction, in the ON state. The switching functionality is verified by the finite-difference time-domain simulation.