Low-energy exciton pocket at finite momentum in tetracene molecular solids
Low-energy exciton pocket at finite momentum in tetracene molecular solids
复制标题
并四苯分子固体中有限动量的低能激子袋
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
M. Knupfer
中科院分区：
文献类型：
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作者：
F. Roth;Markus Nohr;S. Hampel;M. Knupfer
有机半导体中的激发态动力学在许多与光吸收和发射相关的过程中起着重要的作用。我们研究了四烯分子固体中最低单重态激子的动量依赖性，四烯分子固体是其他有机半导体的原型系统。我们的结果揭示了这些激子在有限动量下具有能量最小的各向异性带结构，即低能激子袋。这种低能态的存在可能对光物理行为产生重要影响，也考虑到在有机太阳能电池等方面的应用。我们的研究强调了有机系统中动量依赖因素的重要性。
The excited state dynamics in organic semiconductors plays an important role for many processes associated with light absorption and emission. We have studied the momentum dependence of the lowest singlet excitons in tetracene molecular solids, an archetype system for other organic semiconductors. Our results reveal an anisotropic band structure of these excitons with an energy minimum at finite momentum, i.e., a low-energy exciton pocket. The existence of such low-energy states might have important consequences for the photophysical behavior, also in view of applications in, e.g., organic solar cells. Our studies stress the importance of momentum-dependent considerations in organic systems.