Tamura Hiroyuki, Ramon John G S, Bittner Eric R, Burghardt Irene
Département de Chimie, Ecole Normale Supérieure, 24 rue Lhomond, F-75231 Paris cedex 05, France.
Phys Rev Lett. 2008 Mar 14;100(10):107402. doi: 10.1103/PhysRevLett.100.107402. Epub 2008 Mar 12.
A quantum-dynamical analysis of exciton dissociation at polymer heterojunctions is presented, using a hierarchical electron-phonon model parametrized for three electronic states and 28 vibrational modes. Two representative interfacial configurations are considered, both of which exhibit an ultrafast exciton decay. The efficiency of the process depends critically on the presence of intermediate bridge states, and on the dynamical interplay of high- vs low-frequency phonon modes. The ultrafast, highly nonequilibrium dynamics is consistent with time-resolved spectroscopic observations.
本文采用针对三个电子态和28个振动模式参数化的分层电子-声子模型，对聚合物异质结处的激子解离进行了量子动力学分析。考虑了两种具有代表性的界面构型，二者均表现出超快激子衰减。该过程的效率关键取决于中间桥态的存在以及高频与低频声子模式的动力学相互作用。超快、高度非平衡动力学与时间分辨光谱观测结果一致。
