Plasma oscillations in heavy fermion materials.

We calculate the dielectric function of the lattice Anderson model via an auxiliary boson large N method suitably generalized to include the effects of the long range part of the Coulomb interaction. We show that the model exhibits a low lying plasma oscillation at a frequency omega of order the Kondo temperature of the model, in addition to the usual high frequency plasma oscillation. We also analyze the Anderson model without the long range Coulomb interaction, computing the Landau parameter F sub (0s), and showing that the model has a zero sound mode whose velocity we compute. We derive the version of the f sum rule applicable to our model and show our results satisfy it.