# Two-dimensional electronic transport in rubrene: the impact of inter-chain coupling

## TL;DR

This study models rubrene's electronic transport using coupled 1D chains, revealing that even weak inter-chain coupling significantly enhances charge propagation, which is crucial for optimizing organic semiconductor performance.

## Contribution

The paper introduces a simplified tight-binding model for rubrene that captures the effects of inter-chain coupling on electronic transport properties.

## Key findings

- Weak inter-chain coupling improves charge propagation along chains.
- The model reproduces mobility anisotropy and terahertz conductivity.
- Strong inter-chain coupling is key for optimal transport in organic semiconductors.

## Abstract

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.