Integrated Low-Loss, High-Isolation, and Broadband Magneto-Optical Isolator with TE-Mode Input

High-performance optical isolators are key components in photonic integrated circuits, with significant applications in nonlinear optical systems. We propose a design for a TE-mode optical isolator based on the AlGaAs-on-insulator platform. The isolator consists of non-reciprocal phase shift (NRPS) waveguides, reciprocal phase shift (RPS) waveguides, and multi-mode interference (MMI) couplers achieving low loss, high isolation, and wide bandwidth. Numerical simulations show that, at a wavelength of 1550 nm, the device provides a bandwidth of 91 nm at 30 dB isolation. The confinement factors for a magneto-optical (MO) waveguide were analyzed, and a detailed loss analysis revealed a total loss of 1.47 dB and a figure of merit (FoM) of 2.76 rad/dB. The manufacturing tolerances of the isolator are discussed referring to the requirement of stability and reliability in practical applications. This study provides an optimized design for high-performance TE-mode optical isolators in integrated photonic systems, which are well-suited for efficient and stable nonlinear optical applications.