MAPbBr3屬於有機鹵素鈣鈦礦材料，其具有良好的光學表現，故多數應用集中於光電元件，例如電光調變器。其中電光調變器（Electro-Optic Modulator, EOM）的工作原理是基於電光效應（Electro-Optic Effect），這是一種材料在電場作用下其折射率生變化的現象。在實際應用中，電光調變器通常被用於光纖通信系統，用來對傳輸的光信號進行調控，從而提高數據傳輸速率和質量。此外，MAPbBr3這類的鐵電材料可以透過外加電場影響材料內部的電域形式，意即，外加電場可以控制材料內部屬於單一電域或者(有電域壁存在的)多電域形式，而不同的電域形式將會影響系統內部的光路表現。本研究將研究預期透過影響光路表現達到相位調變器的效果，模擬分成兩步驟：第一原理計算：計算材料光學性質，以及COMSOL Multiphysics：模擬單一電域系統中，無折射率差異(無相位調變)的電域中之光路情形；以及多電域系統中，相鄰電域存在折射率差異(有相位調變)導致光路改變的情形。
本研究成功以COMSOL Multiphysics歸納出具穩定且明顯的折射角度變化的體系，包含合適的入射波長以及入射角度，以及不同界面類型對折射情形的影響。

The refraction behavior of incident beam of different wavelengths passing through various DW interfaces at 50 K, 150 K, 200 K, 350 K were simulated via COMSOL Multiphysics. It is anticipated that light paths with no deflection (single domain) or with large angle deflection (multi-domain) can be used to describe the changes in domain distribution under the influence of an external electric field, and further applied to electro-optic modulator applications. This research successfully used COMSOL Multiphysics to establish a system with stable and significant refraction angle variations. This includes identifying suitable incident wavelengths and angles, as well as understanding how different interface types affect the refraction behavior.

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