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Ground and excited states of the bipolaron in two and three dimensions

Y. H. Ruan·Q. H. Chen·M. Bonitz
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Abstract

The properties of large bipolarons in two and three dimensions are investigated by averaging over the relative wavefunction of the two electrons and using the Lee-Low-Pines-Huybrechts variational method. We obtain the ground-state (GS) and excited-state energies of the Fröhlich bipolaron for the whole range of electron-phonon coupling constants. Furthermore, we calculate the energies of the first relaxed excited state (RES) and Franck-Condon (FC) excited state of the bipolaron. Compared with the FC state, the first RES has a lower energy. Our results for the GS and RES energies are lower than those obtained before by the Landau-Pekar method in the whole coupling regime.

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Y. H. Ruan, Q. H. Chen, M. Bonitz. 2005-09-09. Ground and excited states of the bipolaron in two and three dimensions. https://arxiv.org/abs/cond-mat/0509233

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