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arXiv · 1704.08519

Breakdown of Polarons in Conducting Polymers at Device Field Strengths

M. R. Mahani·A. Mirsakiyeva·Anna Delin
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Abstract

Conducting polymers have become standard engineering materials, used in manyelectronic devices. Despite this, there is a lack of understanding of the microscopicorigin of the conducting properties, especially at realistic device field strengths. Wepresent simulations of doped poly(p-phenylene) (PPP) using a Su-Schrieffer-Heeger(SSH) tight-binding model, with the electric field included in the Hamiltonian througha time-dependent vector potential via Peierls substitution of the phase factor. We findthat polarons typically break down within less than a picosecond after the field hasbeen switched on, already for electric fields as low as around 1.6 mV/{\AA}. This is a fieldstrength common in many flexible organic electronic devices. Our results challenge therelevance of the polaron as charge carrier in conducting polymers for a wide range ofapplications.

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M. R. Mahani, A. Mirsakiyeva, Anna Delin. 2017-04-27. Breakdown of Polarons in Conducting Polymers at Device Field Strengths. https://doi.org/10.1021/acs.jpcc.7b02368

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