2001/08/02 by S. Caprara, C. Di Castro, S. Fratini +1 · 2 citations
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Theoretical and Computational Physics #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.88.147001
5 pages, 3 figures
arxiv created 2001/08/02 · openalex publication_date 2002/03/20 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We argue that the hump observed in the optical conductivity at or below a few hundreds of cm^\ensuremath-1, in overdoped cuprates such as the electron-doped Nd_2\ensuremath-xCexCuO_4\ensuremath-y at x\ensuremath\gtrsim0.15 and the hole-doped Bi2Sr2CuO6 and La_2\ensuremath-xSrxCuO4, cannot be accounted for within a single-fluid description. We propose instead an interpretation based on the direct excitation of charge collective modes, which become nearly critical in the proximity to a charge-ordering instability. Their critical character entails a peculiar temperature dependence and a pseudoscaling form of the optical spectra, which agree with the experimental data.