當前對於波長不敏感的元件需求日益增大，無論是在光纖通訊，或是醫學光學感測上，本論文設計與製作出在SOI平台上具有160-nm頻寬的串接式馬赫詹德方向耦合器(Cascaded Mach-Zehnder Directional Coupler, CMZDC)，此乃於傳統MZDC (Mach-Zehnder Directional Coupler)的基礎架構下，進一步進行改良。本論文使用基因演算法(Genetic Algorithm)與串接多級馬赫詹德干涉器來進增加MZDC的工作頻寬，並提出關於相移器的改良，在設計上以不同寬度的波導來取代，藉以降低其元件大小，也使得光學設計與模擬上更加有效率。此元件也能夠設計出任意分光比，且其具有大頻寬、低損耗的優點。
我們以馬赫詹德干涉儀做為基礎，結合CMZDC來應用於光纖通訊與醫學感測領域中：於光纖通訊400-Gb/s通訊的應用中，本論文設計以多個平頂寬帶的MZI串接的一對四波長分波多工器(Demultiplexer, DEMUX)，以及應用於醫學感測的光學同調斷層掃描的掃頻式濾波器。
在量測20-nm通道寬度的1x4平頂帶寬濾波器，除了一段晶格濾波器受製程誤差造成頻譜兩個通道失真外，其餘兩級晶格濾波器皆具有8-dB以下的串擾。

The wavelength-independent components is in high demand in the optical communication and optical sensing. In this thesis the cascaded Mach-Zehnder directional coupler (CMZDC) is demonstrated with 160-nm bandwidth on the silicon-on-insulator (SOI) platform. The Genetic Algorithm is further utilized to enhance the operating wavelength range. The phase shifter is replaced by waveguides with two different widths to reduce device size and improve simulation efficiency. The CMZDC can be any splitting ratios, and owns the advantages of large bandwidth and low loss.
The CMZDC based Mach-Zehnder interferometer can be taken as the demultiplexer for 400-Gb/s fiber optic communications and biosensing. In this thesis a 1x4 wavelength demultiplexer with flat-top passband is demonstrated. Moreover, the CMZDC is also applied to the swept source of optical coherence tomography (OCT) for higher axial resolution.
A 1x4 flat-top passband demultiplexer with 20-nm channel spacing demonstrates the crosstalk lower than 8-dB except one output due to the process error.

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