本論文中，我們設計五氧化二鉭(Ta2O5)高階模態耦合器，將入射之TE00基本模態耦合至TE10高階模態，以此解決高階模態入射波導效率不足的問題，以五氧化二鉭為材料的波導，其高階模態在波長為1056nm之下，會產生異常色散的現象，經過一系列的非線性效應，能夠產生超連續光譜(Supercontinuum)。
我們以絕熱捷徑理論來進行五氧化二鉭耦合器的設計，進而減少在絕熱條件下所需要的耦合長度，縮小元件的尺寸，根據模擬結果顯示，我們所設計的耦合器在目標波長1056nm下， 耦合效率皆超過99%，選擇的波導厚度為650nm與800nm，所設計的STA耦合器分別有190nm與140nm的頻寬，在波長為1056nm下，製程容忍度方面則分別具有±20nm與±13nm。

The main purpose of this study is to design tantalum pentoxide (Ta2O5) coupler, which couple the input TE00 fundamental mode to the TE10 higher-order mode, to solve the low efficiency problem of higher-order mode coupling by direct excitation. The Ta2O5 waveguide could show anomalous dispersion at a wavelength of 1056nm. After a series of nonlinear effects, it could produce a supercontinuum. To reduce the size of the coupler, we apply the shortcuts to adiabaticity (STA) to design the Ta2O5 coupler. The designed STA coupler has a bandwidth of 190 nm (140 nm) and a fabrication tolerance of ±20nm (±13nm) for 650 nm (800 nm) thick waveguide.

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