Sokolovskii Ilia, Groenhof Gerrit
Nanoscience Center and Department of Chemistry, University of Jyväskylä, P.O. Box 35, 40014 Jyväskylä, Finland.
Nanophotonics. 2024 Jan 16;13(14):2687-2694. doi: 10.1515/nanoph-2023-0684. eCollection 2024 Jun.
Placing a material inside an optical cavity can enhance transport of excitation energy by hybridizing excitons with confined light modes into polaritons, which have a dispersion that provides these light-matter quasi-particles with low effective masses and very high group velocities. While in experiments, polariton propagation is typically initiated with laser pulses, tuned to be resonant either with the polaritonic branches that are delocalized over many molecules, or with an uncoupled higher-energy electronic excited state that is localized on a single molecule, practical implementations of polariton-mediated exciton transport into devices would require operation under low-intensity incoherent light conditions. Here, we propose to initiate polaritonic exciton transport with a photo-acid, which upon absorption of a photon in a spectral range not strongly reflected by the cavity mirrors, undergoes ultra-fast excited-state proton transfer into a red-shifted excited-state photo-product that can couple collectively with a large number of suitable dye molecules to the modes of the cavity. By means of atomistic molecular dynamics simulations we demonstrate that cascading energy from a photo-excited donor into the strongly coupled acceptor-cavity states via a photo-chemical reaction can indeed induce long-range polariton-mediated exciton transport.
将一种材料置于光学腔内，可以通过将激子与受限光模式杂化形成极化激元，从而增强激发能的传输。极化激元具有一种色散特性，能为这些光与物质的准粒子提供低有效质量和非常高的群速度。在实验中，极化激元的传播通常由激光脉冲引发，这些激光脉冲被调谐为与在许多分子上离域的极化激元分支共振，或者与局域在单个分子上的未耦合的高能电子激发态共振。然而，将极化激元介导的激子传输实际应用于器件中，则需要在低强度非相干光条件下运行。在此，我们提议用一种光酸来引发极化激元激子传输，这种光酸在吸收腔内镜未强烈反射的光谱范围内的光子后，会经历超快的激发态质子转移，形成一个红移的激发态光产物，该产物能与大量合适的染料分子集体耦合到腔的模式上。通过原子分子动力学模拟，我们证明了通过光化学反应将光激发供体的能量级联到强耦合受体 - 腔态中，确实可以诱导长程极化激元介导的激子传输。
