Design of a hybrid mode and wavelength division (de)multiplexer based on contra-directional grating assisted couplers on the SOI platform

Abstract

This paper presents a hybrid mode and wavelength division (de)multiplexer (MDM-WDM), based on the silicon-on-insulator platform using the grating assisted contra-directional coupling principle. The proposed hybrid MDM-WDM is able to (de)multiplex six channels with two wavelengths and three modes. The proposed device is designed by cascading three grating assisted coupler sections. Each coupler section is dedicated to reflecting a specific mode at two wavelengths. The operation of the proposed design is simulated by the 2.5D finite-difference time-domain technique. The analysis shows that the proposed device structure exhibits an insertion loss of &lt;<!-- 0.55 d B , return loss of &gt; 12.81 d B , extinction ratio of &gt; 15.49 d B , and crosstalk of &lt;<!-- − 12.74 d B . A fabrication tolerance study for the MDM-WDM device is also performed by changing the inter waveguide distance between the respective multimode bus waveguide and the single-mode waveguide.

Harnessing Anti‐Parity‐Time Phase Transition in Coupled Topological Photonic Valley Waveguides

“…The effective dissipation (i.e., the reflected light) of the APT phases is further harnessed by exploiting the topological robustness and enables an unusual photonic topological bi-functional device, which is challenging to be realized in conventional contra-directional couplers. [47][48][49][50][51] We further close the zigzag waveguide and form a triangular-shaped topological resonator. The topological robustness ensures no reflection or localization by the sharp corners.…”

Silicon‐photonic four‐mode triple‐band multiplexing device for hybrid wavelength/mode division multiplexing networks

“…In such hybrid networks, mode-and-wavelength multiplexers and demultiplexers based on PIC are certainly inevitable. Therefore, many researches have focused on this topic, [26][27][28][29][30][31][32][33] including recent advances showing a mode-and-wavelength multiplexing of up to 32 channels 31,32 or even 80 channels. 33 However, most of the reported researches were mainly demonstrated for wavelength channels multiplexed densely within C band and the multiple band mode multiplexing remain important for further researches as it helps to combine optical bands, for example, O, S, and C bands, of densely multiplexed channels.…”