Design and analysis of ultralow voltage graphene on the silicon rich nitride tunable ring resonator-based add-drop filter for DWDM systems

Abstract

We propose and simulate a third-order 3D electro-optically highly tunable compact add-drop flter based on nonlinear microring resonators. Te used tuning mechanism relies on enhanced Kerr nonlinearity in a graphene layer integrated on top of a two- photonabsorption-free and low loss silicon-rich nitride core material at telecommunication wavelengths. An ultrahigh tuning efciency (150 pm/V) over a tuning range of 1.3 nm, ensuring ultralow voltage consumption, was achieved in this work. We used titanium oxide and silicon oxide as the upper-cladding and under-cladding materials, respectively, around the silicon-rich nitride core material, to come up with a polarization-insensitive, and the thermally resilient third-orderadd-drop optical flter in the L band (1565 nm–1625 nm) with a full wave at a half maximum bandwidth of 50 GHz (linewidth of 0.4 nm) around 1570 nm, a high- free spectral range of 18.5 nm, a quality factor of 2580, an extinction ratio of 60 dB, a fnesse of 19, and a thermal stability of 0.3 pm/ K. A three-dimensional multiphysics approach was used to simulate the propagation of transverse electric and transverse magnetic polarized waves through the flter, combining the electromagnetic features with thermo-optic and stress-optical efects. Te contribution of this work to the existing literature is that the designed flter proposes a new and highly tunable material system compatible with the complementary metal-oxide-semiconductor fabrication technology while combining high tunability, po- larization insensitivity, and high thermal stability features for an ultracompact and energy-efcienton-chip integrated photonic tunable flter for dense wavelength division multiplexing systems in the less occupied L band