微米圓盤的雙重光子奈米噴流現象研究

本論文主要研究微米圓盤經由雙光束(雷射波長405 nm、532 nm、671 nm)照射下，產生的雙重光子奈米噴流現象。微米圓盤使用半導體微影製程和翻模技術來製作，其材料為聚二甲基矽氧烷。本實驗使用數值模擬和實驗量測來研究和證明在不同直徑的微米圓盤和不同雙光束夾角的情況下，光子奈米噴流的變化。在數值模擬方面，使用時域有限差分法來模擬不同直徑、不同雙光束夾角，在不同波長的雙光束(雷射波長405 nm、532 nm、671 nm)照射下，產生的光場分佈及能量強度的情況。在實驗量測方面，使用高靈敏度光學顯微系統來擷取雙重光子奈米噴流的影像，再以電腦程式分析實驗影像之數據，如噴流焦距、距離、半高全寬、能量強度等，並與數值模擬的模擬結果做交互比較。本研究中的雙重光子奈米噴流具對稱性，且會形成中間能量強度為零的間隔，這個間隔的特性可以讓我們透過不同參數的控制來觀測較複雜的外貌。

關鍵字

光子奈米噴流；雙光子奈米噴流；繞射極限

並列摘要

In this paper, the phenomenon of photonic nanojets generated by spherical microdisks while exposes under double beam wavelengths (405 nm, 532 nm, 671 nm) are investigated. Semiconductor manufacturing technologies and molding techniques are adopted to make the microdisks which composes of polydimethylsiloxane . Both numerical simulation and experimentation are presented to discuss the change of the nanojets under different double beam angles and different diameter of microdisks. In the numerical analysis, to simulate the intensity and distribution of photonic nanojets, three different parameters are taken into consideration, i.e. diameters of different microdisks, incident double beam angles, and laser wavelengths (405nm, 532nm, 671nm). In the experimental measurements, a highly sensitive optical microscope system is used to capture the images of the nanojets. A computer program is written to analyze the parameters of photonic nanojets, including focal length, distance, full width at half maximum , and intensity. The results of the simulation and experiment are then compared in this paper. The twin nanojets generated in this paper exhibits a symmetric characteristic and are separated by an intensity null. This intensity null can help us better observe complex external structures through controlling multiple variables.

並列關鍵字

Photonic nanojets ； twin photonic nanojets ； Diffraction limit

參考文獻

[1] J.-P. Berenger, “A perfectly matched layer for the absorption of electromagnetic waves”, Journal of Computational Physics, vol. 114, no. 2, pp. 185-200, 1994