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Dynamical study on polaron formation in a metal/polymer/metal structure

C. Q. Wu·Y. Qiu·K. Nasu
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Abstract

By considering a metal/polymer/metal structure within a tight-binding one-dimensional model, we have investigated the polaron formation in the presence of an electric field. When a sufficient voltage bias is applied to one of the metal electrodes, an electron is injected into the polymer chain, then a self-trapped polaron is formed at a few hundreds of femtoseconds while it moves slowly under a weak electric field (not larger than $% 1.0\times 10^4$ V/cm). At an electric field between $1.0\times 10^4$ V/cm and $% 8.0\times 10^4$ V/cm, the polaron is still formed, since the injected electron is bounded between the interface barriers for quite a long time. It is shown that the electric field applied at the polymer chain reduces effectively the potential barrier in the metal/polymer interface.

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C. Q. Wu, Y. Qiu, K. Nasu. 2003-05-21. Dynamical study on polaron formation in a metal/polymer/metal structure. https://doi.org/10.1103/physrevb.68.125416

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