光學網路基礎研究---子計畫一：全光網路中光子晶體光緩衝器及雙穩態開關之研究

Abstract

本計畫研究著重在全光網路實現上的關鍵元件光子晶體光緩衝器，我們將利用有 限時域差分法(Finite-Difference Time-Domain, FDTD)模擬光子晶體非線性效應所造成 的動態折射率改變來設計光子晶體結構，並藉由製程開發製作實際元件以及利用高解 析高速光電子量測系統量測元件特性， 以期突破目前受限於延遲- 帶寬積 (Delay-Bandwidth Product)的光子晶體能帶邊緣(Band-edge)效應所能達成的1/100 光延 遲，以滿足未來全光網路中光緩衝器所需的延遲等級。本計畫同時也將研究另一關鍵 元件-全光式光子晶體雙穩態開關，針對其在克服傳統非線性雙穩態開關尺寸無法縮小 化，過大的切換功率，以及過慢的切換速度等等缺點上的優勢進行研究。除了在模擬 以及實際元件特性上的雙穩態特性探討外，我們同時也將設計並製作具有基本邏輯操 作的元件，以期未來與光緩衝器在同一結構上整合，並實現全光網路中的全光式光緩 衝器單元。

In this project, we will focus on the realization of photonic crystal optical buffers in all-optical networks. The finite-difference time-domain (FDTD) method is used to simulate the dynamic index variation caused by the photonic crystal non-linear effect. We will design the photonic crystal patterns according to the simulated results. The real devices will be fabricated by our well-developed fabrication process and characterized by high-speed electro-optical measurement system. To satisfy the delay level in real all-optical networks, the propagation delay of the new design should be slower than the 1/100 delay level caused by photonic band-edge effect which is limited by the delay-bandwidth product. We will also focus on another key device, all-optical photonic crystal bi-stable switches. We will investigate on the overcoming of disadvantages in conventional non-linear bi-stable switches including large size in cascade devices, high switching power, and slow switching time. The bi-stable behavior will be characterized both in simulations and measurements. In addition, the photonic crystal bi-stable switches with basic logic functions will be designed to integrate with optical buffers on a single chip. The all-optical buffer unit in all-optical networks can be expected in the near future.