Effect of Pressure on Heavy-Fermion Metals

In this paper, we introduce a microscopic theory for the heavy-fermion metals under applied pressure in the framework of the slave-boson mean-field approximation of the U = ∞ Anderson lattice model. The density of states for ƒ electrons and its variation with the pressure are calculated self-consistently The pressure-dependencies of the low-temperature specific-heat coefficient, magnetic susceptibility, and the resistivity in the electron-type and hole-type heavy-fermion metals are obtained. The results provide a unified explanation on the two opposite pressure-dependent effects observed in Ce-based and Yb-based compounds.