关键词：太阳能电池;高吸收薄膜;梯度法;电磁优化
摘 要：This thesis explores ways to create highly efficient, thin-film solar cells. Both high short circuit current density and high open circuit voltage are required for high efficiency in photovoltaics. High current is achieved by absorbing most of the above bandgap photons, and then extracting the resulting electrons and holes. To achieve high absorption in thin films, surface texturing is necessary. Surface texturing allows for absorption enhancement due to total internal reflection, known as light trapping. However, in subwavelength-thick solar cells, the theory of light trapping is not understood, and both the maximum achievable absorption and the optimal surface texture are open questions. Computational electromagnetic optimization is used to find surface textures yielding an absorption enhancement of 40 times the absorption in a flat solar cell, the highest enhancement achieved in a subwavelength-thick solar cell with a realistic index of refraction. The optimization makes use of adjoint gradient methods, which allow the problem of designing a 3D surface to be computationally tractable.