Presentation Information

[22p-12A-4]Structural Optimization of Thin-Film LNOI Waveguide Grating Couplers

〇(B)Ryosei Kitahara1, Naoki Tahara1, Toshihiko Baba1 (1.Yokohama Nat'l Univ)


Thin-Film LNOI Waveguide

The TFLN waveguide is gaining attention as one of the next-generation optical integrated platforms, but achieving high efficiency in the connection between TFLN waveguides and standard grating couplers for single-mode optical fibers remains a challenge. In this study, a structure feasible through a two-step etching process was designed using Lumerical FDTD optical propagation simulations and Covariance Matrix Adaptation Evolution Strategy (CMA-ES). As a result of the optimization, the emitted light was enhanced in the upward direction, and the coupling efficiency at a wavelength of 1550 nm reached 59.5% (loss of 2.3 dB or less).