Hall effect in the normal state of high-Tc cuprates

We propose a model for explaining the results of the Hall effect measurements of high-T-c cuprates in the normal state, in various materials. They all show common features: a decrease of the Hall coefficient RH with temperature and a universal law, when plotting R-H(T)/R-H (T-0) versus T/T-0 where T-0 is defined from experimental results. This behaviour is explained by using the well known electronic band structure of a CuO2 plane, showing saddles points at the energies E-S in the directions [0, +/-pi] and [+/-pi, 0]. This is well confirmed by photoemission experiments. We remark that for the energies E > E-S the carrier orbits are hole-like and for E < E-S they are electron-like, giving opposite contributions to R-H. We are able to fit all experimental results for all doping, and to fit the universal curve. For us k(B) To is Simply E-F - E-S, where EF is the Fermi level varying with the doping. (C) 2004 Elsevier B.V. All rights reserved.