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arXiv · 1805.04914

Global Equilibrium and Non-Equilibrium Theory of Hopping Exciton Transport in Disordered Semiconductors

Mehdi Ansari-Rad·Stavros Athanasopoulos
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Abstract

We develop a temperature dependent theory for singlet exciton hopping transport in disordered semiconductors. It draws on the transport level concept within a Förster transfer model and bridges the gap in describing the transition from equilibrium to non-equilibrium time dependent spectral diffusion. We test the validity range of the developed model using kinetic Monte Carlo simulations and find agreement over a broad range of temperatures. It reproduces the scaling of the diffusion length and spectral shift with the dimensionless disorder parameter and describes in a unified manner the transition from equilibrium to non-equilibrium transport regime. We find that the diffusion length in the non-equilibrium regime does not scale with the the third power of the Förster radius. The developed theory provides a powerful tool for interpreting time-resolved and steady state spectroscopy experiments in a variety of disordered materials, including organic semiconductors and colloidal quantum dots.

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Mehdi Ansari-Rad, Stavros Athanasopoulos. 2018-05-13. Global Equilibrium and Non-Equilibrium Theory of Hopping Exciton Transport in Disordered Semiconductors. https://doi.org/10.1103/physrevb.98.085204

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