论文标题
在光电膜中的影响电离过程：声音耗散的影响
Impact ionization processes in a photodriven Mott insulator: influence of phononic dissipation
论文作者
论文摘要
我们研究了在存在声音子的情况下由莫特绝缘层组成的光伏能量收集模型，并在不同的化学电位处耦合到两个宽带费米铅，并通过周期性电场驱动到非平衡稳态。我们使用所谓的辅助主方程方法将电子相关性与非平衡动力学平均场理论（DMFT）视为杂质求解器，并包括通过Migdal近似通过声音声子耗散。对于与导线的小杂交，我们在光电流中获得峰值，这是驱动频率的函数，这可能与撞击电离过程有关。对于较大的杂交，浅峰表明抑制了直接光伏激发的影响电离。声音子在小驱动频率方面略微增强了光电流，并以所有考虑的杂交强度在主峰周围以频率抑制它。
We study a model for photovoltaic energy collection consisting of a Mott insulating layer in presence of acoustic phonons, coupled to two wide-band fermion leads at different chemical potentials and driven into a nonequilibrium steady state by a periodic electric field. We treat electron correlations with nonequilibrium dynamical mean-field theory (DMFT) using the so-called auxiliary master equation approach as impurity solver and include dissipation by acoustic phonons via the Migdal approximation. For a small hybridization to the leads, we obtain a peak in the photocurrent as a function of the driving frequency which can be associated with impact ionization processes. For larger hybridizations the shallow peak suggests a suppression of impact ionization with respect to direct photovoltaic excitations. Acoustic phonons slightly enhance the photocurrent for small driving frequencies and suppress it at frequencies around the main peak at all considered hybridization strengths.
