Yalouz Saad, Pouthier Vincent
Institut UTINAM, Université de Franche-Comté, CNRS UMR 6213, 25030 Besançon Cedex, France.
Phys Rev E. 2020 Jan;101(1-1):012310. doi: 10.1103/PhysRevE.101.012310.
Using a tight binding model, we investigate the dynamics of an exciton on a disordered extended star graph whose central site acts as an energy trap. When compared with what happens in an ordered network, our results reveal that the disorder drastically improves the excitonic absorption that becomes complete. Moreover, we show the occurrence of an optimal disorder for which the absorption time is strongly minimized, a surprising effect that originates in a disorder-induced restructuring process of the exciton eigenstates. Finally, we also show the existence of an optimal value of the absorption rate that reduces even more the absorption time. The resulting superoptimized trapping process is interpreted as a positive interplay between both the disorder and the so-called superradiance transition.
利用紧束缚模型，我们研究了无序扩展星型图上激子的动力学，该图的中心位点充当能量陷阱。与有序网络中的情况相比，我们的结果表明，无序显著提高了激子吸收并使其变得完全。此外，我们展示了存在一个最优无序，对于该无序吸收时间被极大地最小化，这一惊人效应源于激子本征态的无序诱导重构过程。最后，我们还展示了存在一个吸收速率的最优值，它能进一步缩短吸收时间。由此产生的超优化俘获过程被解释为无序与所谓的超辐射跃迁之间的积极相互作用。
