Special Condensed Matter Seminar, Dan Dessau, Electronic Interactions in Cuprate High-Temperature Superconductors – an ARPES study

Tue, Feb 25, 2014, 1:15 pm to 2:30 pm
PCTS Seminar Room
Using high resolution ARPES we analyze the electronic scattering rates of cuprate superconductors as a function of temperature, energy, and doping. In the normal state we show the smooth and continual evolution from the heavily overdoped Fermi liquid limit to the optimally doped Marginal Fermi liquid limit and beyond, with these results showing a new type of universality for these non-Fermi liquid interactions. These results are also very relevant for discussions of the pseudogap as well as possible quantum-criticality under the dome. We also consider how these self-energy terms affect the superconducting state, focusing not just on the pairing energy scale (the gap ) but also scattering terms that cause pair-breaking. In contrast to conventional superconductors in which the superconducting transition temperature Tc is set by the pairing energy alone, we show that Tc in the cuprates is set by a crossover between the pairing and pair-breaking energy scales, each of which is strongly temperature-dependent.