非对称型Y分支波导是用于实现分支波导光功率非均分输出的重要单元器件, 在集成光子器件中有广泛应用。基于全内反射原理, 提出了一种新型非对称Y分支波导, 通过将左右分支波导相对于输入波导在横向方向上进行偏移以实现特定分束比光输出, 并对其光学特性进行模拟分析。结果表明, 该波导结构不仅能实现任意特定分束比光输出, 在分支角达到14°条件下其输出损耗仅为0.417 dB, 而且偏振依赖性低、工艺制作难度小, 这种新型非对称Y分支波导在集成光子器件中具有重要应用意义。

Asymmetric Y-branch waveguides are important passive components for unequal power splitting, and are widely used in integrated optical circuit. Based on total internal reflection, novel asymmetric Y-branch waveguide is proposed, in which there is little horizontal offset distance between the branch point of the two branch waveguides and the axe of the input waveguide, and the branching ratio can be controlled by changing offset distance. Its optical characteristic is thoroughly investigated by using finite difference beam propagation method(FD-BPM). The simulated results show that arbitrary branching ratio can be realized, and the optical power loss is only 0.417 dB while the branching angle is 14°. This novel asymmetric Y-branch waveguides with low polarization dependence can be easily fabricated, and have more advantages than previously designed ones while being used in integrated optical devices.