本論文利用有限差分時域法探討在雙傳輸導線上藉由奈米電漿子來產生非線性效應(二倍頻)的現象，包括非線性訊號在波導裡面傳遞的模態種類、不同入射模態對於產生二倍頻效應的影響。
而在樣品的製作上，我們使用聚焦離子束的方法將結構刻在微小金片上，實驗觀測的部分，則是利用自行搭設的前半部共聚焦顯微鏡系統以及後半部光學成像系統來進行量測。入射光源為中心1560奈米且脈衝寬約為60飛秒的脈衝雷射，將雷射聚焦在雙傳輸導線的端點上並且利用NIRCCD來觀察基頻激發亮點的位置，接著利用EMCCD觀察二倍頻亮點的位置，同時也使用光譜儀量測二倍頻的光譜訊號，最後我們可以從實驗中觀察到儘管入射的基頻模態不同(橫向電波模態以及橫向磁波模態)，但產生出來的二倍頻模態卻都是屬於橫向磁波模態(TM)。接著將實驗結果和模擬結果互相比較，確定為二倍頻訊號。

In this work, we used finite-difference time-domain (FDTD) numerical analysis to investigate the generation of nonlinear response (second harmonic generation, SHG) by surface plasmonics on the two-wire transmission line (TWTL), including the mode type of propagating nonlinear signals, the effect of different input fundamental mode type on the generation of SHG.
We used focused ion beam milling to fabricate the samples which deposited on the glass substrate, and in the experiment, we used our home-made confocal microscope and the other optical system. A pulse laser with center wavelength 1560 nm and about 60 fs pulse duration is focused on the spot at the end of TWTL and NIR CCD camera is used to observe the position of fundamental emission spot. As for SHG signal, we used EMCCD to observe it, and we also used the spectrometer to detect the spectrum of SHG signal. Finally, we found that despite the input fundamental mode is different, the mode type of generated SHG signals are both TM mode.

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