本論文建立一套以熱銣原子中鑽石型能階結構為基礎的雙光子產生系統，利用波長分別為 795 奈米與 1475 奈米的耦合光與驅動光激發四波混頻過程，成功產生波長為 780 奈米與 1529 奈米、具時間關聯性的光子對。在理論方面，本研究建構一套考慮都卜勒展寬效應的四能階鑽石型自發四波混頻開放量子模型，以模擬熱原子蒸氣中光子對的產生行為與時間關聯特性，並預測不同實驗參數下的系統表現。實驗上，首先透過熱原子二能階吸收譜掃描，量測不同溫度下的光學深度，作為調整系統參數之依據。隨後以耦合光與驅動光同時激發熱原子蒸氣，誘發鑽石型能階結構中的自發四波混頻效應以產生光子對，並使用兩組單光子偵測器與飛行時間探測器進行偵測與延遲時間分析。經評估收光效率、背景雜訊與系統穩定性等限制因素後，實驗結果在產生率與時間關聯寬度方面均與理論預測一致。本研究驗證熱原子系統具備實現可見光與通訊波段間雙光子對產生的可行性，展現其於未來量子通訊應用中的發展潛力。

In this thesis, we develop a photon-pair generation system based on the diamond-type energy level structure in hot rubidium atoms. By employing coupling and driving laser fields with wavelengths of 795 nm and 1475 nm, respectively, we induce a four-wave mixing process that generates time-correlated photon pairs at wavelengths of 780 nm and 1529 nm. On the theoretical side, we construct an open quantum model for spontaneous four-wave mixing in a four-level diamond-type system, explicitly incorporating Doppler broadening, to simulate the generation dynamics and temporal correlations of photon pairs in a thermal atomic vapor. This model further enables us to predict the system's behavior under various experimental conditions. Experimentally, we first perform Doppler-broadened absorption spectroscopy on a two-level atomic transition to measure the optical depth at different temperatures, which serves as a reference for optimizing system parameters. The photon pairs are then generated by simultaneously exciting the atomic vapor with the coupling and driving lasers, and detected using two single-photon detectors and a time-of-flight analyzer. After evaluating limiting factors such as collection efficiency, background noise, and system stability, the measured photon-pair generation rate and temporal correlation width are found to be consistent with theoretical predictions. These results confirm the feasibility of generating photon pairs bridging the visible and telecommunication bands using thermal atomic systems, demonstrating their potential for future quantum communication applications.

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