Missaoui Ahmed, Khabthani Jouda Jemaa, Trambly de Laissardière Guy, Mayou Didier
Laboratoire de Spectroscopie Atomique Moléculaire et Applications, Département de Physique, Faculté des Sciences de Tunis, Université de Tunis El Manar, Campus Universitaire, 1060 Tunis, Tunisia.
Laboratoire de Physique théorique et Modélisation, CNRS and Université de Cergy-Pontoise, 95302 Cergy-Pontoise, France.
Entropy (Basel). 2019 Feb 28;21(3):233. doi: 10.3390/e21030233.
Organic semi-conductors have unique electronic properties and are important systems both at the fundamental level and also for their applications in electronic devices. In this article we focus on the particular case of rubrene which has one of the best electronic transport properties for application purposes. We show that this system can be well simulated by simple tight-binding systems representing one-dimensional (1D) chains that are weakly coupled to their neighboring chains in the same plane. This makes in principle this rubrene system somehow intermediate between 1D and isotropic 2D models. We analyse in detail the dc-transport and terahertz conductivity in the 1D and in the anisotropic 2D models. The transient localisation scenario allows us to reproduce satisfactorily some basics results such as mobility anisotropy and orders of magnitude as well as ac-conductivity in the terahertz range. This model shows in particular that even a weak inter-chain coupling is able to improve notably the propagation along the chains. This suggest also that a strong inter-chain coupling is important to get organic semi-conductors with the best possible transport properties for applicative purposes.
有机半导体具有独特的电子特性，无论是在基础层面还是在电子器件应用方面都是重要的体系。在本文中，我们聚焦于红荧烯这一特殊情况，它具有适用于应用目的的最佳电子输运特性之一。我们表明，该体系可以通过简单的紧束缚体系得到很好的模拟，这些紧束缚体系代表着在同一平面内与相邻链弱耦合的一维（1D）链。这原则上使得该红荧烯体系在某种程度上介于一维和各向同性二维模型之间。我们详细分析了一维和各向异性二维模型中的直流输运和太赫兹电导率。瞬态局域化情形使我们能够令人满意地重现一些基本结果，如迁移率各向异性、数量级以及太赫兹范围内的交流电导率。该模型特别表明，即使是弱的链间耦合也能够显著改善沿链的传播。这也表明对于获得具有适用于应用目的的最佳可能输运特性的有机半导体而言，强的链间耦合很重要。
