Cesium–formamidinium-based mixed-halide perovskite materials with optical band gaps ranging from 1.5 to 1.8 eV are investigated by variable-angle spectroscopic ellipsometry. The determined complex refractive indices are shown to depend on the fabrication procedure and environmental conditions during processing. This data is complemented by additional optical and structural characterization, as well as the demonstration of efficient perovskite solar cells. Finally, the data is used in optical simulations to provide guidelines for the optimization of perovskite/silicon tandem solar cells.

中文翻译：

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铯-甲ami基混合卤化物钙钛矿的复折射指数，光学带隙为1.5至1.8 eV

用可变角度光谱椭圆偏振光法研究了铯-甲ami基混合卤化物钙钛矿材料，其光学带隙范围为1.5至1.8 eV。所确定的复折射率显示为取决于制造过程和加工过程中的环境条件。附加的光学和结构表征，以及高效钙钛矿太阳能电池的演示，为该数据提供了补充。最后，将数据用于光学仿真，以提供优化钙钛矿/硅串联太阳能电池的指南。