Temperature dependence of Hall coefficient in high-Tc oxides

Large Fermi surfaces obtained by the local-density band-structure calculation are consistent with signs of the Hall coefficient obtained by experiment for almost all high-Tc oxide superconductors. However, a simple band-electron picture cannot explain the large temperature dependence of the Hall coefficient. We propose a phenomenology for the temperature dependence of the Hall coefficient, and discuss the origin of temperature dependences of transport coefficients.