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arXiv · 2411.17460

High-precision Quantum Monte-Carlo study of charge transport in a lattice model of molecular organic semiconductors

Pavel Buividovich·Johann Ostmeyer·Alessandro Troisi
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Abstract

We use first-principle Quantum Monte-Carlo (QMC) simulations and numerical exact diagonalization to analyze the low-frequency charge carrier mobility within a simple tight-binding model of molecular organic semiconductors on a two-dimensional triangular lattice. These compounds feature transient localization, an unusual charge transport mechanism driven by dynamical disorder. The challenges of studying the transient localization of charge carriers in the low-frequency/long-time limit from first principles are discussed. We demonstrate that a combination of high-precision QMC data with prior estimates of frequency-dependent charge carrier mobility based on the static disorder approximation for phonon fields allows for improved estimates of mobility in the low-frequency limit. We also point out that a simple relaxation time approximation for charge mobility in organic semiconductors is not consistent with the QMC data. Physical similarities with charge transport in quark-gluon plasma are highlighted.

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Pavel Buividovich, Johann Ostmeyer, Alessandro Troisi. 2024-11-26. High-precision Quantum Monte-Carlo study of charge transport in a lattice model of molecular organic semiconductors. https://doi.org/10.22323/1.466.0067

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