The non-equilibrium stationary coherences that form in donor–acceptor systems are investigated to determine their relationship to the efficiency of energy transfer to a neighboring reaction center. It is found that the effects of asymmetry in the dimer are generally detrimental to the transfer of energy. Four types of systems are examined, arising from combinations of localized trapping, delocalized (Forster) trapping, eigenstate dephasing, and site basis dephasing. In the cases of site basis dephasing, the interplay between the energy gap of the excited dimer states and the environment is shown to give rise to a turnover effect in the efficiency under weak dimer coupling conditions. Furthermore, the nature of the coherences and associated flux is interpreted in terms of pathway interference effects. In addition, regardless of the cases considered, the ratio of the real part and the imaginary part of the coherences in the energy-eigenbasis tends to a constant value in the steady state limit.

中文翻译：

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自然非相干光下的能量转移：不对称对效率的影响。

研究了在供体-受体系统中形成的非平衡平稳相干，以确定它们与能量转移到相邻反应中心的效率之间的关系。发现二聚体中的不对称作用通常不利于能量转移。检查了四种类型的系统，这些系统是由局部陷井，离域（福斯特）陷井，本征相移相和位点基础移相的组合产生的。在基于位相移相的情况下，在弱二聚体耦合条件下，被激发的二聚体态的能隙与环境之间的相互作用显示出对效率的转换效应。此外，用路径干扰效应来解释相干性和相关通量的性质。此外，无论考虑哪种情况，