9603111.pdf (130.6 kB)
Boson-fermion model beyond mean-field approximation
preprint
posted on 2006-04-04, 10:29 authored by A.S. AlexandrovA model of hybridized bosons and fermions is studied beyond the mean field approximation. The divergent boson self-energy at zero temperature makes the Cooper pairing of fermions impossible. The frequency and momentum dependence of the self- energy and the condensation temperature $T_{c}$ of initially localized bosons are calculated analytically. The value of the boson condensation temperature $T_{c}$ is below $1K$ which rules out the boson-fermion model with the initially localized bosons as a phenomenological explanation of high-temperature superconductivity. The intra-cell density-density fermion-boson interaction dominates in the fermion self-energy. The model represents a normal metal with strongly damped bosonic excitations. The latter play the role of normal impurities.
History
School
- Science
Department
- Physics
Pages
133730 bytesPublication date
1996Notes
This is a pre-print. It is also available at: http://arxiv.org/abs/cond-mat/9603111.Language
- en