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arXiv · 1606.02219

A translation invariant bipolaron in the Holstein model and superconductivity

Victor Lakhno
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Abstract

Large-radius translation invariant (TI) bipolarons are considered in a one-dimensional Holstein molecular chain. Criteria of their stability are obtained. The energy of a translation invariant bipolaron is shown to be lower than that of a bipolaron with broken symmetry. The results obtained are applied to the problem of superconductivity in 1D-systems. It is shown that TI-bipolaron mechanism of Bose-Einstein condensation can support superconductivity even for infinite chain.

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Victor Lakhno. 2017-02-02. A translation invariant bipolaron in the Holstein model and superconductivity. https://doi.org/10.1186/s40064-016-2975-x

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