Abstract and subjects
We present a systematic study at ambient pressure of the phononic and electronic Raman-active excitations in the ab plane of the (Ce,La)MIn5 (M=Co,Rh) heavy-fermion family. We found that the characteristic Raman spectra of this family of compounds display two phonon modes at similar to 38 and similar to 165 cm(-1) and a broad electronic background centered at similar to 40 cm(-1). For CeCoIn5, the temperature dependence of these excitations shows anomalous behavior near T-*=45 K that may indicate a nontrivial renormalization of the electronic structure driven by strong correlations between hybridized 4f electrons.