Reconfigurable optical add-drop multiplexer at 1550 nm using magnetically-coupled switches based on a photonic crystal

Abstract

In this paper, a design of reconfigurable optical add-drop multiplexer (ROADM) is proposed, which consists of magnetically-coupled switches, bus waveguide, drop waveguide, add waveguide, and reflection cavity based on a photonic crystal (PC). The ferrite materials are introduced to form microcavities in a two-dimensional PC. Then, the magnetic permeability of ferrite rods is changed by adjusting the magnetic field strength, and a scheme for magnetic permeability distribution of magnetically-coupled switches is proposed. The simulation results indicate that the incident wave with wavelength 1550 nm can be downloaded and uploaded successfully, and the transmissivity of wave is both above 90% when the add function and drop function are conducted. The quality (Q) factor is approximately 103. Moreover, the overall size of the device is 13.5 μm× 10.5 μm, which is highly suitable for wavelength division multiplexing (WDM) system in the photonic integrated circuits.