Effect of Incommensurate Charge-Density Wave Scattering on the Electronic Structure of High-Tc Cuprates

We argue that the collective mode as observed in angle resolved photoemission spectroslopy (ARPES) on a large class of cuprates can be associated with dynamic incommensurate CDW fluctuations present in these materials. This scenario is substantiated by a comparison of calculated spectra with experimental ARPES data where we obtain a mode frequency that decreases toward optimal doping, thus strongly supporting the existence of a quantum critical point around this concentration. Moreover, we extract the temperature dependence of the associated bosonic spectrum from ARPES data, where it turns out that there is a continuous evolution from mode-type behavior below T _c to a marginal Fermi liquid structure well above T _c.