EFFECTS OF DOPING ON HYBRIDIZATION GAPPED MATERIALS

Doping studies are presented on three materials exhibiting hybridization gaps: Ce3Bi4Pt3, U3Sb4Pt3 and CeRhSb. In the case of trivalent La, Y, or Lu substituting for Ce or U, there is a suppression of the low temperature gap and an increase in the electronic specific heat, gamma. In the case of tetravalent Th substitutions for U there is no change in gamma and in the case of tetravalent Zr substitution for Ce in CeRhSb, there is an enhanced semiconductor-like behavior in the electrical resistance. These results are discussed in the light of a simple model of hybridization gapped systems.