论文标题
由不连贯的光驱动的光收获能量转移的稳态分析：从二聚体到网络
Steady-State Analysis of Light-harvesting Energy Transfer Driven by Incoherent Light: From Dimers to Networks
论文作者
论文摘要
在科学界，量子相干如何促进能源转移的问题是在激烈的争论中。由于天然和人造的光收获单元在固定条件下运行，因此我们通过对不连贯的阳光照射的分子二聚体的非平衡稳态分析来解决这个问题，然后将关键预测推广到任意复杂的激子网络。稳态分析的主要结果是连贯的 - 效率关系：$η= c \ sum_ {i \ neq j} f_ {ij}κ_j= 2c \ sum_ {i \ neq j}在这个关系中，第一个平等表明，能量传递效率$η$由捕获通量唯一决定，这是通量$ f $和分支比率$κ$用于捕获反应中心的乘积，第二均等的等值表明能量传递$ f $是量子相等的量子，以量化的量子量相等。 $ f_ {ij} = 2J_ {ij} {\ rm im} [ρ_{ij}] $。因此，最大稳态相干性带来了最佳效率。相干 - 频率效率的关系在固定条件下的任意连通性的任何激子网络都严格且通常保持不变，并且不仅限于不连贯的辐射或不连贯的泵送。对于在不连贯的光线下进行的轻度收获系统，非平衡能量传递通量（即稳态相干）是由详细平衡的分解和光渗透的量子干扰驱动的，并导致能量传递效率的优化。应当指出的是，稳态相干性或等效地，效率是光引起的瞬态相干性，无均匀耗竭和系统培养基相关性的综合结果，因此不一定与量子击败相关。
The question of how quantum coherence facilitates energy transfer has been intensively debated in the scientific community. Since natural and artificial light-harvesting units operate under the stationary condition, we address this question via a non-equilibrium steady-state analysis of a molecular dimer irradiated by incoherent sunlight and then generalize the key predictions to arbitrarily-complex exciton networks. The central result of the steady-state analysis is the coherence-flux-efficiency relation:$η=c\sum_{i\neq j}F_{ij}κ_j=2c\sum_{i\neq j}J_{ij}{\rm Im}[ρ_{ij}]κ_j$ with $c$ the normalization constant. In this relation, the first equality indicates that energy transfer efficiency $η$ is uniquely determined by the trapping flux, which is the product of flux $F$ and branching ratio $κ$ for trapping at the reaction centers, and the second equality indicates that the energy transfer flux $F$ is equivalent to quantum coherence measured by the imaginary part of the off-diagonal density matrix, i.e., $F_{ij}=2J_{ij}{\rm Im}[ρ_{ij}]$. Consequently, maximal steady-state coherence gives rise to optimal efficiency. The coherence-flux-efficiency relation holds rigorously and generally for any exciton networks of arbitrary connectivity under the stationary condition and is not limited to incoherent radiation or incoherent pumping. For light-harvesting systems under incoherent light, non-equilibrium energy transfer flux (i.e. steady-state coherence) is driven by the breakdown of detailed balance and by the quantum interference of light-excitations and leads to the optimization of energy transfer efficiency. It should be noted that the steady-state coherence or, equivalently, efficiency is the combined result of light-induced transient coherence, inhomogeneous depletion, and system-bath correlation, and is thus not necessarily correlated with quantum beatings.
