We report on the theoretical investigation and optimization of optical coupling performance between Si₃N₄ waveguide and Ge-based waveguide via an amorphous Ge_xSi lateral linear taper. Different compositions of the amorphous tapers including amorphous Si (0% Ge), amorphous Ge_0.60Si_0.40 (60% Ge), and amorphous Ge_0.83Si_0.17 (83% Ge) are investigated over various telecommunication wavelength values of 1310 nm (O-band), 1410 nm (E-band), 1495 nm (S-band), 1550 nm (C-band), and 1595 nm (L-band). Si₃N₄ waveguide dimensions with different values of width and thickness are also studied. From the analysis, competitive optical coupling performance from the amorphous lateral tapers were found to be obtainable over the entire wavelength ranges by changing only the taper end width and length. This work demonstrates that the coupling structure can be potentially employed for low-loss wideband optical integration between two Si-based waveguide components with relatively high refractive index contrast over the entire telecommunication regions.

我们报告了通过无定形Ge _x Si横向线性锥度在Si ₃ N ₄波导和Ge基波导之间进行光耦合性能的理论研究和优化。在1310 nm的各种电信波长值下，研究了包括非晶Si（0％Ge），非晶Ge _0.60 Si _0.40（60％Ge）和非晶Ge _0.83 Si _0.17（83％Ge）的非晶锥度的不同组成。波段），1410 nm（E波段），1495 nm（S波段），1550 nm（C波段）和1595 nm（L波段）。硅₃ N ₄还研究了具有不同宽度和厚度值的波导尺寸。通过分析，发现仅改变锥形端部的宽度和长度，就可以在整个波长范围内获得无定形横向锥度的竞争性光耦合性能。这项工作表明，该耦合结构可以潜在地用于两个硅基波导组件之间的低损耗宽带光学集成，并且在整个电信领域具有相对较高的折射率对比度。