A detailed balance calculation reveals an extremely high efficiency of 63.2% for intermediate-band solar cells (IBSCs) under maximum sunlight concentration. However, an actual IBSC device with an efficiency larger than the Shockley-Queisser (SQ) limit has so far not been reported. The main difficulties lie in realizing an efficient sequential two-photon absorption (STPA) which requires a sufficiently long lifetime intermediate state or intermediate band. In this article, we propose the concept of a ratchet type IBSC, utilizing a long lifetime of rare-earth ion luminescence centers in Erbium-doped GaAs. The temperature dependent differential external quantum efficiency reveals a significant STPA contribution originating from the Er³⁺ luminescence center. All the results were modeled and interpreted by integrating the ratchet effect with up-conversion along with a density functional theory (DFT) simulation. Our work demonstrates that the long lifetime energy-transfer mechanism in Er³⁺ centers contributes directly to the formation of a ratchet type IB.

详细的平衡计算表明，在最大日照浓度下，中频带太阳能电池（IBSC）的效率极高，为63.2％。但是，到目前为止，尚未有效率高于Shockley-Queisser（SQ）极限的实际IBSC设备的报告。主要困难在于实现有效的顺序双光子吸收（STPA），这需要足够长的使用寿命的中间态或中间带。在本文中，我们提出了棘轮式IBSC的概念，它利用了掺Er GaAs中稀土离子发光中心的长寿命。温度相关的微分外部量子效率揭示了源自Er ³⁺的显着STPA贡献发光中心。通过结合棘轮效应和上转换以及密度泛函理论（DFT）仿真，对所有结果进行建模和解释。我们的工作表明，Er ³⁺中心的长寿命能量传递机制直接有助于形成棘轮IB型。