先前之研究中，對於完美導體情況下的狹縫漏斗效應已有較為完整的了解，然而對於真實金屬情況下的狹縫漏斗效應仍待研究。本研究主要探討在不同ω_p(plasma frequency)的情況下，其金屬狹縫下的漏斗效應，並以我們所定義之漏斗形狀，進一步分析此情況下之漏斗效應。此研究所設定之ω_p較接近於入射光之ω，不似完美導體差至15個數量級以上。於此情況下，我們發現其Ey場之相位轉變時間相較於Hz有所延遲，之後也如完美導體隨著週期震盪，進而發現漏斗在一個週期內存在的時間會明顯地減少，且涵蓋之範圍減少，同時也可以看到狹縫內時間平均的能量流有明顯的減少。

From previous studies, we have a more complete understanding about the funneling effect of slit in the case of perfect electric conductor (PEC). However, the real metal’s funneling effect still needs to be studied. In this thesis, we focus on the funneling effect under the metal slit with different plasma frequencies. Then, we use the definition of funnel shape from previous work to study funneling effect’s characteristic further. In this thesis, we let the material’s plasma frequency near our light source’s angular frequency. It does not resemble the perfect conductor difference to more than 15 orders of magnitude. In this case, the diffraction wave’s phase changing will be a delay compared to the PEC case. In the case of ω_p⁄ω_0 =3, its diffracted wave will also oscillate with the cycle. Then, the time that the funnel presented in one cycle is significantly reduced, and its covering area is also reduced. The time average energy flow is also reduced at the same time.

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