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Instability due to long range Coulomb interaction in a liquid of polarizable particles (polarons, etc.)

J. Lorenzana
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Abstract

The interaction Hamiltonian for a system of polarons a la Feynman in the presence of long range Coulomb interaction is derived and the dielectric function is computed in mean field. For large enough concentration a liquid of such particles becomes unstable. The onset of the instability is signaled by the softening of a collective optical mode in which all electrons oscillate in phase in their respective self-trapping potential. We associate the instability with a metallization of the system. Optical experiments in slightly doped cuprates and doped nickelates are analyzed within this theory. We discuss why doped cuprates matallize whereas nickelates do not.

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J. Lorenzana. 1999-11-08. Instability due to long range Coulomb interaction in a liquid of polarizable particles (polarons, etc.). https://doi.org/10.1209/epl%2Fi2001-00185-0

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