https://doi.org/10.1007/s100510050717
Electronic and magnetic structure of the undoped two and three-leg ladder cuprates in an itinerant electrons model
1
Laboratoire Surfaces et Supraconducteurs, École Supérieure de Physique et Chimie
Industrielles de la ville de Paris,
10 rue Vauquelin, 75231 Paris Cedex 5, France
2
Groupe de Physique des Milieux Denses, UFR Sciences - Université Paris XII,
61 avenue du Général de Gaulle,
94010 Créteil Cedex, France
Received:
3
June
1998
Published online: 15 April 1999
We study the electronic and magnetic structure of the undoped ideal two and
three-leg ladder cuprates by assuming a moderate on site coulombic repulsion.
This analysis is an extension of the Fermi liquids studies proposed for the CuO2
plane in view to explain the high Tc superconductivity and the competition with the
antiferromagnetic phase. At zero doping, the quasi-one-dimensionality of the structure
results in SDW correlations with different (commensurate) vectors according to the
number of legs, which contrasts with the predictions made from the Heisenberg model.
At mean field, and for n = 3 (Sr2Cu3O5), we predict a magnetic ordered
state, detected by μSr and NMR measurements with critical temperatures consistent
with our assumptions on the physical parameters, the modulation vector being .
The presence of several bands at the Fermi level explains why there is no observable
gap in the static susceptibility measurements. For n = 2, we predict a gap
consistent with experimental Curie susceptibility. But the expected magnetic
instability is detected only in La2Cu2O5, where the interladder coupling is
stronger. In every case the one-dimensional van Hove singularities are far from the
Fermi level, making difficult the obtaining of high Tc superconductivity.
PACS: 74.70.-b – Superconducting materials (excluding high-Tc compounds) / 74.20.-Fg – Superconducting materials (excluding high-Tc compounds) / 75.10.-Lp – Band and itinerant models
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 1999