Hybridization gap insulating behavior of ${\mathrm{Ce}}_3$${\mathrm{Bi}}_4$${\mathrm{Pt}}_3$

We have calculated the temperature dependence of various thermodynamic and transport properties for the N=2 single-band insulating phase of the Anderson lattice Hamiltonian using a slave-boson approach. The conduction band was assumed to be parabolic with a spherical Brillouin-zone boundary. The transport properties were calculated assuming an impurity scattering mechanism and using a relaxation-time approximation. Our calculations demonstrate how many-body effects (on-site Coulomb repulsion) cause an otherwise wide-gap material to behave as a very-narrow-gap material with temperature dependence in qualitative agreement with the experimental data for ${\mathrm{Ce}}_3$ ${\mathrm{Bi}}_4$ ${\mathrm{Pt}}_3$. This calculation supports the view that this material is an indirect-gap semiconductor.