Since their advent around the start of the millennium, hot carrier solar cells came into the focus of a broader research community as one of the so-called 3$^{\rm{rd}}$ generation photovoltaic concepts. As an exciting research field enthusiastically covered by an increasing number of publications, some aspects of hot carrier solar cell research, namely data interpretation and conclusions with respect to high efficiency devices, appear to show some discrepancies. It therefore appeared timely to provide a detailed review of current hot carrier solar cell research from the fundamentals of non-equilibrium carrier dynamics to complete solar cells to enable advancement with the knowledge of solid state and semiconductor physics being fully taken into account. In our work, we discuss the hot carrier non-equilibrium dynamics right from the process of hot carrier generation, going beyond the standard 1-dimensional approach, hence exploring phononic and other dynamic limits as occurring in real materials. Thermodynamic modelling of hot carrier solar cells in the literature presented conversion efficiencies from 0.04 to 84 \%. This situation called for an evaluation and a comparison against the Shockley-Queisser efficiency limit. The assessment of characterisation techniques used for dynamic and steady-state detection of hot carrier populations form another part of this review, including to what extent certain data can or should be used in regards to hot carrier solar cells. With this wealth of information, we work through III-V, IV-IV, II-VI, and non-trivial materials which were proposed for hot carrier absorbers in the literature. With the physics and materials considered, we then examine energy-selective contact designs which also have to fulfil the criterion of carrier selectivity. Finally, we look at the whole hot carrier solar cell, departing from the original concept to more feasible designs and qualitatively new approaches.

中文翻译：

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热载流子太阳能电池的非平衡动力学、材料和结构：详细回顾

自千禧年之初问世以来，热载流子太阳能电池作为所谓的 3$^{\rm{rd}}$ 发电概念之一，成为更广泛研究界的焦点。作为一个被越来越多的出版物热情覆盖的令人兴奋的研究领域，热载流子太阳能电池研究的某些方面，即关于高效器件的数据解释和结论，似乎出现了一些差异。因此，从非平衡载流子动力学的基本原理到完整的太阳能电池，对当前的热载流子太阳能电池研究进行详细回顾似乎是及时的，以便在充分考虑固态和半导体物理学知识的情况下取得进步。在我们的工作中，我们从热载流子生成过程开始讨论热载流子非平衡动力学，超越了标准的一维方法，因此探索了真实材料中发生的声子和其他动态限制。文献中热载流子太阳能电池的热力学模型显示转换效率从 0.04 到 84 \%。这种情况需要对肖克利-奎瑟效率极限进行评估和比较。用于动态和稳态检测热载流子群体的表征技术的评估构成了本次审查的另一部分，包括某些数据可以或应该在多大程度上用于热载流子太阳能电池。凭借这些丰富的信息，我们通过 III-V、IV-IV、II-VI、以及文献中提出的用于热载流子吸收器的非平凡材料。考虑到物理和材料，然后我们检查能量选择性接触设计，这些设计也必须满足载流子选择性标准。最后，我们看看整个热载流子太阳能电池，从最初的概念转向更可行的设计和质量上的新方法。