Abstract
Evidence of polaron formation in superconducting cuprates is provided by infrared reflectivity spectra. In the Nd-Ce-Cu-O with T-c approximate to 20 K, polaron formation corresponds to vibrational local modes in the far-infrared and to a band in the mid-infrared built up through overtones and combination bands of these modes. A comparison with infrared spectra taken by different groups on Y-Ba-Cu-O, and Tl-Sr-Ca-Cu-O suggests that polarons survive in the highest-T-c superconductors.