Exact formulas of diagonal conductivity $\sigma_{ xx}$ and Hall conductivity $\sigma_{ xy}$ are derived from the Kubo formula in hybridized two-orbital systems with arbitrary band dispersions. On the basis of the theoretical framework for the Fermi liquid based on these formulas, the ground-state properties of the periodic Anderson model with electron correlation and weak impurity scattering are studied on the square lattice. It is shown that imbalance of the mass-renormalization factors in $\sigma_{ xx}$ and $\sigma_{ xy}$ causes remarkable increase in the valence-fluctuation regime as the f level increases while the cancellation of the renormalization factors causes slight increase in $\sigma_{ xx}$ and $\sigma_{ xy}$ in the Kondo regime. The Hall coefficient $R_{ \rm H}$ shows almost constant behavior in both the regimes. Near half filling, $R_{ \rm H}$ is expressed by the total hole density as $R_{ \rm H}=1/(\bar{ n}_{ \rm hole}e)$ while $R_{ \rm H}$ approaches zero near quarter filling, which reflects the curvature of the Fermi surface. These results hold as far as the damping rate for f electrons is less than about $10~\%$ of the renormalized hybridization gap. From these results we discuss pressure dependence of residual resistivity and normal Hall effect in Ce- and Yb-based heavy electron systems.
Categories: cond-mat.str-el