MEAN-FIELD RESULTS FOR THE KONDO LATTICES AT HIGH MAGNETIC-FIELDS

We generalize previous slave-boson mean-field calculations for the Kondo lattices to high magnetic fields, and derive analytic expressions for the Kondo energy when the hybridization matrix element is isotropic. For the anisotropic case, two metamagneticlike transitions are found, and their relative strength depends on the number of electrons participating in the hybridization per unit cell. We discuss the implications for this to the metamagneticlike transition and its related properties in heavy-fermion compounds. In particular, the relative motion of different spin bands is considered to reproduce the field dependence of the residual magnetoresistance.