论文标题
不重的光引起的激发收获的非平衡稳态图片
Nonequilibrium steady-state picture of incoherent light-induced excitation harvesting
论文作者
论文摘要
我们制定了通过弱不连贯辐射激发分子聚集体激发收获的全面理论描述。开发了一种有效的数值方案，该方案尊重激发通量的连续性方程，以计算由激发产生，激发弛豫，脱落，在负载下陷阱和重组之间的相互作用引起的非平衡稳态（NESS）。在所谓的优先基础上，最方便地描述了NESS，在该基础上，稳态激子密度矩阵是对角线的。通过将优选的基本描述与站点或激子碱基中的描述相关联，可以检查NESS属性。专注于模型的光合二聚体，我们发现长期捕获时间极限的NES与激发态平衡非常相似，在该平衡中，固定的连贯性源自激发环境的纠缠。对于较短的捕获时间，我们演示了如何从不连贯驱动但卸载的二聚体的时间相关描述中提取NES的属性。如果陷阱时间比在飞秒光谱实验中可访问的动态连贯性的衰减时间更长，则静止图片和时间依赖性图片之间的这种关系是有效的。
We formulate a comprehensive theoretical description of excitation harvesting in molecular aggregates photoexcited by weak incoherent radiation. An efficient numerical scheme that respects the continuity equation for excitation fluxes is developed to compute the nonequilibrium steady state (NESS) arising from the interplay between excitation generation, excitation relaxation, dephasing, trapping at the load, and recombination. The NESS is most conveniently described in the so-called preferred basis in which the steady-state excitonic density matrix is diagonal. The NESS properties are examined by relating the preferred-basis description to the descriptions in the site or excitonic bases. Focusing on a model photosynthetic dimer, we find that the NESS in the limit of long trapping time is quite similar to the excited-state equilibrium in which the stationary coherences originate from the excitation-environment entanglement. For shorter trapping times, we demonstrate how the properties of the NESS can be extracted from the time-dependent description of an incoherently driven but unloaded dimer. This relation between stationary and time-dependent pictures is valid, provided that the trapping time is longer than the decay time of dynamic coherences accessible in femtosecond spectroscopy experiments.
