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arXiv · 1008.2735

Key pairing interaction in layered doped ionic insulators

A. S. Alexandrov·A. M. Bratkovsky
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Abstract

A controversial issue on whether the electron-phonon interaction (EPI) is crucial for high-temperature superconductivity or it is weak and inessential has remained one of the most challenging problems of contemporary condensed matter physics. We employ a continuum RPA approximation for the dielectric response function allowing for a selfconsistent semi-analytical evaluation of the EPI strength, electron-electron attractions, and the carrier mass renormalisation in layered high-temperature superconductors. We show that the Fröhlich EPI with high-frequency optical phonons in doped ionic lattices is the key pairing interaction, which is beyond the BCS-Migdal-Eliashberg approximation in underdoped superconductors, and it remains a significant player in overdoped compounds.

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A. S. Alexandrov, A. M. Bratkovsky. 2010-08-16. Key pairing interaction in layered doped ionic insulators. https://doi.org/10.1103/physrevlett.105.226408

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