Due to the large difference in mode size and effective-index mismatch between the optical fiber and the waveguides on the photonic integrated circuits, it is a big challenge to efficiently couple light into thin semiconductor waveguides. In this paper, a taper plasmonic coupler is presented to couple fiber light into an Si waveguide. The taper plasmonic coupler structure is optimized, and the alignment tolerance of the gap, the lateral offset and the vertical offset between coupler and Si waveguide are studied. Numerical simulation shows that the coupler changes the single mode fiber light to multimode light at its input port section, while at its output port section, the coupler turns the multimode light back to a single mode light, and finally couples this light to Si waveguide. The maximum couple efficiency is 86.8% in [Formula: see text] effective coupler length.

中文翻译：

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基于等离子体器件的光纤到波导耦合

由于光纤和光子集成电路上的波导之间的模式尺寸和有效折射率不匹配的巨大差异，将光有效地耦合到薄半导体波导中是一个巨大的挑战。在本文中，提出了一种锥形等离子体耦合器，用于将光纤耦合到硅波导中。对锥形等离子体耦合器结构进行了优化，研究了间隙的对准公差、耦合器与硅波导之间的横向偏移和垂直偏移。数值模拟表明，耦合器在其输入端口部分将单模光纤光变为多模光，而在其输出端口部分，耦合器将多模光变回单模光，并最终将该光耦合到硅波导。[公式：