https://doi.org/10.1140/epjb/e2003-00335-8
Charge density plateaux and insulating phases in the t-J model with ladder geometry
1
Physics Department, University of Wuppertal, 42097 Wuppertal,
Germany
2
Institute for Advanced Studies in Basic Sciences,
Zanjan 45195-159, Iran
Corresponding author: a fledderj@physik.uni-wuppertal.de
Received:
10
December
2002
Revised:
28
July
2003
Published online:
8
December
2003
We discuss the occurrence and the stability of charge density plateaux in
ladder-like systems (at zero magnetization M=0) for the cases
of 2- and 3-leg ladders. Starting from isolated rungs at zero leg coupling,
we study the behaviour of plateaux-related phase transitions by means of
first order perturbation theory and compare our results with Lanczos
diagonalizations for
ladders (
) with increasing leg couplings.
Furthermore we discuss the regimes of rung and leg couplings that should be
favoured for the appearance of the charge density plateaux.
PACS: 71.10.Fd – Lattice fermion models (Hubbard model, etc.) / 71.27.+a – Strongly correlated electron systems; heavy fermions / 75.10.-b – General theory and models of magnetic ordering / 75.10.Jm – Quantized spin models
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2003