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arXiv · 1307.8096

Phonon-enhanced relaxation and excitation in the Holstein-Hubbard model

Philipp Werner·Martin Eckstein
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Abstract

We study quenches of the interaction and electron-phonon coupling parameter in the Hubbard-Holstein model, using nonequilibrium dynamical mean field theory. The calculations are based on a generalized Lang-Firsov scheme for time-dependent interactions or externally driven phonons, and an approximate strong-coupling impurity solver. The interaction quench calculations reveal the phonon-assisted decay of excess doublons, while the quenches of the electron-phonon coupling lead to persistent oscillations of the phonons and to a phonon-enhanced doublon production.

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Philipp Werner, Martin Eckstein. 2013-07-30. Phonon-enhanced relaxation and excitation in the Holstein-Hubbard model. https://doi.org/10.1103/physrevb.88.165108

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