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arXiv · 1510.06912

Renormalized energy of ground and first excited state of Fröhlich polaron in the range of weak coupling

M. V. Tkach·Ju. O. Seti·O. M. Voitsekhivska·O. Yu. Pytiuk
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Abstract

Partial summing of infinite range of diagrams for the two-phonon mass operator of polaron described by Fröhlich Hamiltonian is performed using the Feynman-Pines diagram technique. Renormalized spectral parameters of ground and first excited (phonon repeat) polaron state are accurately calculated for a weak electron-phonon coupling at $T=0$ K. It is shown that the stronger electron-phonon interaction shifts the energy of both states into low-energy region of the spectra. The ground state stays stationary and the excited one decays at a bigger coupling constant.

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M. V. Tkach, Ju. O. Seti, O. M. Voitsekhivska, O. Yu. Pytiuk. 2015-10-23. Renormalized energy of ground and first excited state of Fröhlich polaron in the range of weak coupling. https://doi.org/10.5488/cmp.18.33707

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