Non-Fermi liquid behavior and scaling of the low-frequency suppression in the optical conductivity spectra of CaRuO3 -: art. no. 041104

Optical conductivity spectra sigma(1)(omega) of paramagnetic CaRuO3 are investigated at various temperatures. At T=10 K, it shows a non-Fermi-liquid behavior of sigma(1)(omega)similar to1/omega(1/2), similar to the case of a ferromagnet SrRuO3. As the temperature (T) is increased, on the other hand, sigma(1)(omega) in the low-frequency region is progressively suppressed, deviating from the 1/omega(1/2) dependence. Interestingly, the suppression of sigma(1)(omega) is found to scale with omega/T at all temperatures. The origin of the omega/T scaling behavior coupled with the non-Fermi-liquid behavior is discussed.