We derive the photovoltaic conversion efficiency limit for two-terminal tandem solar cells with a perovskite top cell and silicon bottom cell with an embedded spectrum splitter. For large-bandgap top-cells, a spectrum splitter strongly enhances the efficiency because of enhanced light absorption and trapping. A Lambertian spectral splitter shows a significantly improved effect compared with a planar splitter. We find an ideal efficiency enhancement for a 500-nm thick top cell of 6% absolute for bandgaps above 1.75 eV. Vice versa, the use of a spectral splitter geometry enables the use of a thinner top cell. Using experimental parameters for perovskite cells, we show that for a top-cell bandgap of 1.77 eV a 2.7% absolute efficiency enhancement can be achieved. The calculations in this work show that integration of a spectral splitter into perovskite/silicon tandem cells for which the top cell is limiting the overall current can lead to a large increase in efficiency, even with realistic experimental losses and nonunity reflection of the spectral splitter.

中文翻译：

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具有平面和朗伯光谱分离器的两端钙钛矿/硅串联太阳能电池的详细平衡效率限制

我们推导出了具有钙钛矿顶部电池和具有嵌入式光谱分离器的硅底部电池的两端串联太阳能电池的光伏转换效率极限。对于大带隙顶部电池，光谱分离器由于增强了光吸收和捕获而大大提高了效率。与平面分光器相比，朗伯光谱分光器显示出显着改善的效果。对于 1.75 eV 以上的带隙，我们发现 500 nm 厚的顶部电池的理想效率提升为 6% 绝对值。反之亦然，光谱分离器几何结构的使用使得能够使用更薄的顶部电池。使用钙钛矿电池的实验参数，我们表明，对于 1.77 eV 的顶部电池带隙，可以实现 2.7% 的绝对效率提升。