DOI: https://doi.org/10.30970/jps.02.236
CHARGE SUSCEPTIBILITY IN STRONGLY CORRELATED ELECTRON SYSTEMS
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Journal of Physical Studies 2(2), 236–240 (1998)
DOI: https://doi.org/10.30970/jps.02.236 CHARGE SUSCEPTIBILITY IN STRONGLY CORRELATED ELECTRON SYSTEMS |
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R. Citro, M. Marinaro
Università degli Studi di Salerno - Unità INFM di Salerno
Dipartimento di Scienze Fisiche ‟E. R. Caianiello", 84081 Baronissi (SA), Italy
We investigate the charge susceptibility in strongly correlated electron systems by using a Bethe-Salpeter equation in a generalized cumulant expansion for the $p$–$d$ model, at varying values of the doping and temperature. We find that for small values of the correlation $U_d$, the charge susceptibility decreases near the half–filling as hole–doping approaches zero, this behavior suggesting the precursor of the Mott–Hubbard gap formation. Particular attention is paid to the role played by the Van Hove singularity near the Fermi level in the density of states, in connection with the unusual normal state properties of the hole–doped cuprates.