Theory of the hall effect in strongly correlated Fermi systems

The anomalous properties of the Hall constant in the normal state of high-T sub(c) superconductors are investigated within the Hubbard model. In Mori theory, the frequency dependent Hall constant is given as the sum of its infinite frequency limit and a memory function contribution. The first term (R super( arrow down )b sub(H) super(!)) was already considered by Shastry et al. In perturbation theory and in the limit of infinite spatial dimensions, the memory function contribution causes the Hall constant to change sign as a function of doping ( delta ) and to decrease as a function of temperature, if we allow U to be approximately 2 W (U: Coulomb repulsion; W: bandwidth). In the limit U arrow right arrow left , the memory function is calculated via its moments. For frequencies W < < T omega < < TU, this leads to a decrease of R super( arrow down )b sub(H) super(!) by a factor of (1+ delta )/2.