積體光學元件應用於光操控微粒子

Optical Manipulation of Micro-particles on Integrated Photonic Devices

許力中(Li-Chung Hsu)

指導教授 ： 李明昌

國立清華大學/電機資訊學院/光電工程研究所/碩士(2012年)

摘要

本論文提出方向耦合器(Directional Coupler)與多模干涉耦合器(Multi-mode Interferometer)的設計流程與製程方式，藉以實現利用光學機制產生的力量驅動以及轉換微粒子移動的軌跡。光波導上的消逝波(Evanescent Wave)將可推動微粒子，而光學元件上之光場分佈將影響微粒子的驅動軌跡，藉以控制微粒子於光學元件上的位置。操作實驗使用50mW TM極化雷射光，以1540nm及1550nm波段用以選擇微粒子流動於不同出口。本論文以MATLAB軟體計算操縱微粒子的力量，並驗證力場分佈情形符合實驗結果。方向耦合器與多模干涉耦合器的耦合長度亦使用MATLAB計算，並於實驗中量測實際耦合長度。經過實驗證實，計算出的耦合長度與實驗結果相符，以此再次印證微粒子移動的軌跡將依隨光學元件上的光場分佈圖形。

關鍵字

方向耦合器 ； 多模干涉耦合器 ； 消逝波 ； 光操控

並列摘要

In this thesis, we present the design and fabrication of directional couplers and multi-mode interferometers (MMI) for realizing micro-particle transport and switch through optical force. The evanescent field of the integrated photonic devices is able to propel a micro-particle to flow and control the trajectory of particle movement, according to the optical field distributed within the devices. By launching the TM polarized laser at the power of 50mW, the micro-particles can be transported to different output ports by selecting wavelengths between 1540nm and 1550nm. Optical force acting on the micro-particle is calculated by MATLAB, and the field of force is used for optical manipulation. Coupling lengths of directional coupler and MMI as a function of optical wavelengths are also analyzed by MATLAB and confirmed by experiments. It shows that the calculated coupling length agrees well with the results of experiments, where the trajectory of the micro-particle follows the optical interference pattern in the photonic device.

並列關鍵字

Directional Coupler ； Multi-mode Interferometer ； Evanescent Wave ； Optical Manipulation

參考文獻

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