Delocalized Two-Exciton States in DNA Scaffolded Cyanine Dimers
Delocalized Two-Exciton States in DNA Scaffolded Cyanine Dimers
复制标题
DOI：
10.1021/acs.jpcb.0c06732
复制
发表时间：
2020-09-17
影响因子：
3.3
通讯作者：
Melinger, Joseph S.
中科院分区：
文献类型：
--
作者：
Cunningham, Paul D.;Diaz, Sebastian A.;Melinger, Joseph S.
离域分子激子态的工程和操纵是人工仿生光捕获复合物以及基于激子传播的替代电路平台的关键组成部分。在这里，我们研究了DNA双工支架上菁二聚体的强电子偶联的后果。距离最近的染料，直接连接在双螺旋上，由于强烈的电子耦合，表现出明显的达维多夫分裂。我们证明了DNA支架足够坚固，可以支持从最低能量（j -类）单激子状态到非局部双激子状态的过渡观察，其中每个花青素染料都处于激发态。这种跃迁通过连续光子吸收进行，并在激子的生命周期内持续存在，将其建立为创建双激子态的受控方法。我们的观察结果表明，dna组织的染料网络具有作为分子逻辑门和基于离域双激子态的纠缠光子发射的平台的潜力。
The engineering and manipulation of delocalized molecular exciton states is a key component for artificial biomimetic light harvesting complexes as well as alternative circuitry platforms based on exciton propagation. Here we examine the consequences of strong electronic coupling in cyanine homodimers on DNA duplex scaffolds. The most closely spaced dyes, attached to positions directly across the double-helix from one another, exhibit pronounced Davydov splitting due to strong electronic coupling. We demonstrate that the DNA scaffold is sufficiently robust to support observation of the transition from the lowest energy (J-like) one-exciton state to the nonlocal two-exciton state, where each cyanine dye is in the excited state. This transition proceeds via sequential photon absorption and persists for the lifetime of the exciton, establishing this as a controlled method for creating two-exciton states. Our observations suggest that DNA-organized dye networks have potential as platforms for molecular logic gates and entangled photon emission based on delocalized two-exciton states.