在光子積體電路中，彎曲波導不可或缺，但在縮小元件尺寸的同時，損耗也會逐漸上升，成為微型化光子元件道路上的絆腳石。於是我們設計出一種基於廣義自適應窗函數(Generalized Adaptive Polynomial Window Function)的彎曲波導模型，能隨著路徑改變寬度的彎曲波導，並透過粒子群優化(Particle Swarm Optimization)演算法運算出在小彎曲半徑(1~3μm)能夠有高效率的彎曲曲線輪廓。
彎曲波導採用絕緣層覆矽結構 (Silicon-On-Insulator, SOI) ，工作頻段在中心波長1550 nm下，並使用3D-FDTD有限時域差分法進行模擬。在起始彎曲半徑為1μm下，一般傳統彎曲波導傳輸效率約為0.9 / 90°，而我們所設計的彎曲波導穿透係數能提升至0.98 / 90°，波導寬度0.45~0.9845μm不等，在2μm彎曲下也成功將波導穿透係數從0.982 / 90°提升至0.997 / 90°，相較目前最令人熟知的彎曲波導優化-進階彎曲波導(Advanced Bend)也有更好的傳輸表現，但是在彎曲半徑大於3μm下並沒有特別突出的性能表現。

In photonic integrated circuits, bent waveguides are indispensable. As devices become smaller in size, the issue of increased energy loss becomes important and hinders the miniaturization of photonic components. To solve this problem, we have developed a model of a bent waveguide using the Generalized Adaptive Polynomial window function and utilize the Particle Swarm Optimization algorithm to compute highly efficient bent curves for small bending radii(1~3 μm).
The waveguide uses the Silicon-On-Insulator (SOI) structure with a central wavelength of 1550 nm and utilizes the 3D-FDTD method in simulations. For radius R=1 μm, the transmission efficiency of traditional bent waveguides is around 0.9 / 90°. However, our designs achieve an improvement in transmittance coefficient of 0.98 / 90°. At R=2 μm, the transmission coefficients improve from 0.982 / 90° to 0.997 / 90°. In comparison to well-known optimized bent waveguide, the Advanced Bend, we can say our design has better performance for smaller bending radii.

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