Open AccessMultimode-based polarization independent WDM devices using different order modes for TE and TM polarizations
Author(s) -
Yosuke Onawa,
Hideaki Okayama,
Daisuke Shimura,
Hiroki Yaegashi,
Hirokazu Sasaki,
Kashima Masayuki
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.412069
Subject(s) - optics , physics , polarization (electrochemistry) , beam splitter , fiber bragg grating , interferometry , power dividers and directional couplers , multi mode optical fiber , wavelength division multiplexing , optoelectronics , wavelength , optical fiber , laser , chemistry
Multimode based polarization independent (PI) wavelength division multiplexing (WDM) devices are proposed and experimentally demonstrated. The key concept is to utilize two different order modes for the orthogonal polarizations, ith-order mode for TE and jth-order mode for TM (i ≠ j) polarization respectively to extend the flexibility for designing devices. PI coupler composed of a multimode directional coupler and mode converters is introduced as a basic device. Then, we apply PI coupler to Mach Zehnder interferometer (MZI) and Bragg grating bandpass filters. PI MZI is achieved by optimizing the combination of two phase shifters in the interferometer arms. PI bandpass uses 3dB-PI coupler and polarization rotate Bragg gratings that induce mode coupling between the polarizations. Each device showed good matching in the spectrum between TE and TM polarizations in term of operation wavelength. The proposed concept can be a promising approach to realize PI WDM functions without introducing polarization diversity scheme in which a polarization beam splitter, two devices designed for each polarization and a polarization beam combiner are required.