Translation-Invariant Excitons in a Phonon Field

Victor D. Lakhno

doi:10.3390/condmat6020020

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arXiv · 2105.09287

Translation-Invariant Excitons in a Phonon Field

Victor D. Lakhno

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Abstract

Large-radius excitons in polar crystals are considered. It is shown that translation invariant description of excitons interacting with a phonon field leads to a nonzero contribution of phonons into the exciton ground state energy only in the case of weak or intermediate electron-phonon coupling. A conclusion is made that self-trapped excitons cannot exist in the limit of strong coupling. Peculiarities of the absorption and emission spectra of translation invariant excitons in a phonon field are discussed. Conditions when the hydrogen-like exciton model remains valid in the case of electron-phonon interaction are found.

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Victor D. Lakhno. 2021-05-06. Translation-Invariant Excitons in a Phonon Field. https://doi.org/10.3390/condmat6020020

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