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arXiv · 1308.2331

Effect of screening of the electron-phonon interaction on the temperature of Bose-Einstein condensation of intersite bipolarons

B. Yavidov·A. Kurmantayev·D. Alimov·B. Kurbanbekov·Sh. Ramonkulov
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Abstract

Here we consider an interacting electron-phonon system within the framework of extended Holstein-Hubbard model at strong enough electron-phonon interaction limit in which (bi)polarons are the essential quasiparticles of the system. It is assumed that the electron-phonon interaction is screened and its potential has Yukawa-type analytical form. An effect of screening of the electron-phonon interaction on the temperature of Bose-Einstein condensation of the intersite bipolarons is studied for the first time. It is revealed that the temperature of Bose-Einstein condensation of intersite bipolarons is higher in the system with the more screened electron-phonon interaction.

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B. Yavidov, A. Kurmantayev, D. Alimov, B. Kurbanbekov, Sh. Ramonkulov. 2013-08-10. Effect of screening of the electron-phonon interaction on the temperature of Bose-Einstein condensation of intersite bipolarons. https://doi.org/10.1140/epjb%2Fe2013-40037-0

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