In common photovoltaic devices, the part of the incident energy above the absorption threshold quickly ends up as heat, which limits their maximum achievable efficiency to far below the thermodynamic limit for solar energy conversion. Conversely, the conversion of the excess kinetic energy of the photogenerated carriers into additional free energy would be sufficient to approach the thermodynamic limit. This is the principle of hot carrier devices. Unfortunately, such device operation in conditions relevant for utilization has never been evidenced. Here, we show that the quantitative thermodynamic study of the hot carrier population, with luminance measurements, allows us to discuss the hot carrier contribution to the solar cell performance. We demonstrate that the voltage and current can be enhanced in a semiconductor heterostructure due to the presence of the hot carrier population in a single InGaAsP quantum well at room temperature. These experimental results substantiate the potential of increasing photovoltaic performances in the hot carrier regime.

在普通的光伏设备中，高于吸收阈值的入射能量部分很快以热量结束，这将其最大可达到的效率限制在远低于太阳能转换的热力学极限的范围内。相反，将光生载流子的过量动能转化为额外的自由能将足以接近热力学极限。这就是热载设备的原理。不幸的是，这种设备在与使用有关的条件下的操作从未被证明过。在这里，我们显示了对热载流子数量的定量热力学研究以及亮度测量，使我们能够讨论热载流子对太阳能电池性能的贡献。我们证明，由于在室温下单个InGaAsP量子阱中存在热载流子，因此可以提高半导体异质结构中的电压和电流。这些实验结果证实了在热载流子状态下提高光伏性能的潜力。