我們利用製做成雙重共振腔的PPKTP晶體，藉由其非線性效應，以及腔模重合頻率的長間隔，試圖架設出一套，架設相對簡易，適合應用在量子訊息科學上的單光子光源，並在實驗上檢測系統產生的雙光子性質。
我們在實驗上驗證其窄頻頻寬，以及其產生生之雙光子間的正相關性，其後尋找能產生與銣原子交互作用光子的晶體溫度。我們在兩個不同pump頻率時，各在兩個晶體溫度下，觀察到雙光子之一能被銣原子吸收；並藉由此結果，與理論模型的趨勢，我們推測出可能使兩光子皆能被銣原子吸收的實驗操作方式。

We fabricated our PPKTP crystal into a doubly-resonant cavity. By utilizing the nonlinear effect of the crystal, and the wide cluster spacing of the cavity, we hoped to construct a relatively simple setup for generation of biphoton source, which is suitable for application in the quantum information science, and furthermore estimated the qualities of our generated photons experimentally.
We experimentally justified the biphotons’ narrow bandwidth and positive correlation; we then searched for the crystal temperature that generates biphotons to have interaction with rubidium atoms. We observed absorption of one of the biphotons by rubidium atoms at two different temperatures each when the pump beam was at two separate frequencies. According to this result and the tendency we found from our simulation model, we came up with a possible way to generate biphotons that can be simultaneously absorbed by rubidium atoms.

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[8]網路資料https://www.sacher-laser.com/applications/overview/absorption_spectroscopy/rubidium_d1.html#TopAnchor