Fermi-liquid phase of the t-J model and the Hall coefficient in high-temperature superconductors

The Hall coefficient in the strongly correlated Fermi-liquid phase of the t-J model is studied for moderate hole concentrations. The quasi-particle self-energy is strongly k-dependent due to gauge-field interactions. It leads to corrections to the Fermi surface curvature and to enhancement of the quasi-particle lifetime in the holelike region. A systematic treatment of the strong local correlations to next-to-leading order in 1/N is sufficient to give rise to a sign change in the Hall coefficient. This effect occurs near 0.20 doping for J/t = 0.2 and thought to be relevant to the high-Tc materials. (Author)