近年來鹵化鉛鈣鈦礦因為其優秀的光電響應，使其在太陽能電池、發光二極管 (Light Emitting Diode, LED)、雷射等光電元件的開發備受關注。其中二維有機-無 機鈣鈦礦因為其對於水以及溫度的穩定性遠超過三維鈣鈦礦，使其具有更高的商業 化潛力。並且因為其結構的特殊性，使其自行成多重量子井結構並將激子受限於的 二維無機層中，並產生較大的激子束縛能，使我們可以在室溫下研究激子－極化子 (Exciton-Polariton) 的現象。
在這項工作中，我們通過溶液法輕鬆的合成了二維有機無機鈣鈦礦單晶薄膜 PEA2PbX4 (phenethylamine PEA, X = Br, I)，並分析二維鈣鈦礦的基本的光學特性。 因為二維鈣鈦礦的結構特性，使其自然形成法布里－佩羅光學腔 (Fabry–Pérot Cavity) 並表現出明顯的腔極化子模式。並且從激子-極化子耦合的能量-向量 (E-k) 色散關係評估拉比分裂能量 (Ω) ，其中 PEA2PbBr4 的拉比分裂能量約為 304 meV， 而 PEA2PbI4 的拉比分裂能量約為 242 meV。藉由研究層狀二維鈣鈦礦的激子極化 子特性，使其可能在強光-物質相互作用區域中應用為極化子元件。

In recent years, lead halide based perovskites have been widely used in the development of optoelectronic device such as solar cells, light emitting diode (LED), and laser, due to their excellent photoelectric response. In addition, the stability of twodimensional (2D) organic-inorganic perovskite to water and temperature is greater then three dimensional (3D) perovskites, and because of its particular structure, a natural multiple quantum well can be formed, which confines the excitons in the 2D inorganic layer. As a result, the exciton binding energy could be higher than the thermal energy of room temperature, which allows us to study the phenomenon of exciton-polariton at room temperature. In this work, we synthesized 2D organic-inorganic perovskite single-crystal thin films PEA2PbX4 (X=Br, I) by solution method and employed X-ray diffraction measurements to study the crystal structure, and analyze the fundamental optical properties of 2D perovskite material by photoluminescence (PL) and Time-Resolved Photoluminescence (TRPL) measurement. The morphological results show that we have successfully grown perovskite single crystals of hundreds of micrometers. The Rabi splitting energy fitting from the calculated energy-wavevector dispersion (E-k dispersion) curve of PEA2PbBr4 and PEA2PbI4 are 304 meV and 242 meV. Compared with other processes to grow single crystals of perovskite, our results are much larger, which mean that we can grow single crystals with higher crystal quality.

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