# Two channel model for optical conductivity of high mobility organic crystals

## TL;DR

This paper models the optical conductivity of high mobility organic crystals like Pentacene and Rubrene, revealing that their carrier dynamics can be described by a superposition of diffusive and localized charge behaviors.

## Contribution

It introduces an approximation-free Monte Carlo approach to analyze carrier scattering by impurities and phonons in organic crystals, providing new insights into their conductivity mechanisms.

## Key findings

- Carrier dynamics differ from conventional metals.
- Optical conductivity can be modeled as a superposition of Drude and Lorentz terms.
- The model accurately describes temperature-dependent conductivity.

## Abstract

We show that the temperature dependence of conductivity of high mobility organic crystals Pentacene and Rubrene can be quantitatively described in the framework of the model where carriers are scattered by quenched local impurities and interact with phonons by Su-Schrieffer-Hegger (SSH) coupling. Within this model, we present approximation free results for mobility and optical conductivity obtained by world line Monte Carlo, which we generalize to the case of coupling both to phonons and impurities. We find fingerprints of carrier dynamics in these compounds which differ from conventional metals and show that the dynamics of carriers can be described as a superposition of a Drude term representing diffusive mobile particles and a Lorentz term associated with dynamics of localized charges.