论文标题
连贯的声子驱动的热载体效应在超晶格太阳能电池中
Coherent Phonons-Driven Hot Carrier Effect in a Superlattice Solar Cell
论文作者
论文摘要
从理论上研究了由极性半导体制成的超晶格太阳能电池中的载体热化，通过考虑一个最小模型，其中电子散射是载体能量损失的主要通道。重要的是，固有的量子机械性能的效果；在半经典图片中，根据声子波包研究了载体热化的声子相干性。事实证明，连贯的纵向光学（LO）声子削弱了有效的电子音波耦合，因此据说降低了太阳能电池中的载体能量损失率。相干的声子确实显着降低了所得的热化功率，从而增强了热载体效应，尤其是对于载流子限制也很强的足够薄的井层。最近，关于超晶格太阳能电池原型的实验显示出了相干语音驱动的现象。我们的结果证明了通过热载体效应，声子在半导体中的基本量子相干性能在半导体中的基本量子相干性能的实际意义。
Carrier thermalization in a superlattice solar cell made of polar semiconductors is studied theoretically by considering a minimal model where electron-phonon scattering is the principal channel of carrier energy loss. Importantly, the effect of an intrinsic quantum mechanical property; the phonon coherence, on carrier thermalization is investigated, within semiclassical picture in terms of phonon wave packet. It turns out that coherent longitudinal optical (LO) phonons weaken the effective electron-phonon coupling, thus supposedly lowering the carrier energy loss rate in solar cell. The resulting thermalization power is indeed significantly reduced by the coherent phonons, resulting in enhanced hot carrier effect, particularly for thin enough well layer where carrier confinement is also strong. A recent experiment on superlattice solar cell prototype is shown to manifest the coherent phonons-driven phenomenon. Our results demonstrate the practical implications of the fundamental quantum coherence property of phonons in semiconductors for improving superlattice solar cell performance, via hot carrier effect.
