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arXiv · 1403.7376

Field-induced polaron formation in the Holstein-Hubbard model

Philipp Werner·Martin Eckstein
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Abstract

We study the effect of strong DC and pulsed electric fields on a Mott insulating system with coupling to optical phonons. A DC field of the order of the gap induces a metallic state characterized by polaronic features in the gap region and a partially inverted population. In this quasi-steady state, the field-induced doublon-hole production is balanced by a phonon-enhanced doublon-hole recombination. The photo-excitation of carriers by a pulsed field leads to similar modifications of the electronic structure in the gap region, and an associated reduction of the doublon life-time. We demonstrate that the field-induced localization of electrons effectively enhances the phonon coupling, an effect which should be measureable with time-resolved photoemission spectroscopy.

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Philipp Werner, Martin Eckstein. 2014-03-28. Field-induced polaron formation in the Holstein-Hubbard model. https://doi.org/10.1209/0295-5075/109/37002

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