單光子和糾纏光子在量子物理學上佔有十分重要的一席之地，其扮演著實現量子電腦與量子密碼學中最重要的基石。所以，產生優秀的糾纏光子源儼然成為了量子光學研究中的核心。過去雖然也有人達成高效率的糾纏光子對，但往往是在Cavity、脈衝雷射等方法下達成。在不使用上述方法時，糾纏光子對的detection rate約為900（1/s/mW）[4-1]。我們利用一台中心波長為532nm的連續式雷射，將其打入一塊非線性光學晶體（KTP晶體），找到了一組高效率的糾纏光子對，其detection rate高達26675（1/s/mW）。這對糾纏光子對為Type II SPDC，兩光子之波長分別為1038nm與1091.2nm。進一步的，在實驗上我們藉由改變不同的實驗架構去觀察這對糾纏光子的不同性質，包含biphoton rate、anticorrelation parameter、spectrum和Franson Interference。

Single and entangled photons, in particular, have now played an important role in quantum physics. They are the most important cornerstone to realize quantum computers and quantum cryptography. It is therefore necessary to develop high-efficiency entangled photon source for studying quantum optics. Although high efficiency entangled photon pairs have been demonstrated, they are often achieved with cavity and pulsed lasers. When not using the above method, the highest reported detection rate of entangled photon pairs is about 900 (1/s/mW). We use continuous wave laser which wavelength is 532nm, focused into a nonlinear optical crystal (KTP crystal). We observed a highly efficient entangled photon pairs with a detection rate up to 26675 (1/s/mW). These entangled photon pairs are of Type II Spontaneous parametric down-conversion, with wavelengths of 1038nm and 1091.2nm. In addition, we use various methods to measure their intensity correlation and to explore their properties, including biphoton rate, anticorrelation parameter, spectrum and Franson Interference.

摘要 i
誌謝 iii
目錄 iv
圖目錄 vi
第1章 實驗目的與動機 1
第2章 基本原理 3
2.1 馬克士威方程組（Maxwell’s equations） 3
2.2 非線性效應 4
2.3 耦合方程組（coupled equation） 6
2.4 糾纏光子（time-energy entanglement photon） 10
2.5 單光子探測儀（Single photon detector） 11
2.6 Coincidence Counts 12
2.7 抗相關性係數（anticorrelation parameter） 16
2.8 Franson interference 19
第3章 實驗參數的估計 26
3.1 Phase matching波長與晶體折射率 26
3.2 糾纏光子對時域上波包寬度 27
3.3 Lens挑選與spot size計算 30
3.4 頻譜 33
3.5 糾纏光子對generation rate 38
第4章 實驗系統架設與測量 40
4.1 實驗架構 40
4.2 anticorrelation parameter（twofold coincidence count） 42
4.3 anticorrelation parameter（threefold coincidence count） 48
4.4 頻譜 50
4.5 Franson interference 53
第5章 討論與總結 59
參考文獻 60

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