Optical studies of the charge-density-wave phase transition in Lu5Rh4Si10

The optical reflectance of the ternary rare-earth intermetallic material Lu5Rh4Si10 has been measured over a wide frequency range (50-55000cm-1) and at temperatures between 15 and 300K. The charge-density-wave (CDW) transition (TCDW∼147K) in this compound manifests itself as a progressive transfer of the Drude spectral weight into the midinfrared absorption bands, leading to the formation of a pseudogap with 2Δ∼5.9kBTCDW. Moreover, calculations of the effective number of electrons from the optical conductivity and the fits to the reflectance indicate that approximately 4% of the Fermi surface is destroyed at TCDW. The rest retains its three-dimensional metallic characters. All of these observables support the suggestion of a strongly coupled CDW transition in Lu5Rh4Si10.