Density of states in locally ordered amorphous organic semiconductors: emergence of the exponential tails

Abstract

We present a simple model of the local order in amorphous organic semiconductors which naturally produces a spatially correlated exponential density of states (DOS). The dominant contribution to the random energy landscape is provided by electrostatic contributions from dipoles or quadrupoles. An assumption of the preferable parallel orientation of neighbor quadrupoles or antiparallel orientation of dipoles directly leads to the formation of the exponential tails of the DOS even for a moderate size of the ordered domains. The insensitivity of the exponential tail formation to the details of the microstructure of the material suggests that this mechanism is rather common in amorphous organic semiconductors.

arXiv comment18 pages, 10 figures

References in corpus (3)

• Theory of the field-effect mobility in amorphous organic transistors
• Distribution of averages in a correlated Gaussian medium as a tool for the estimation of the cluster distribution on size
• Hopping charge transport in amorphous organic and inorganic materials with spatially correlated random energy landscape

Cited by in corpus (1)

• Charge transport in the spatially correlated exponential random energy landscape: effect of the non-positive correlation function