## This Week at Physics |
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### Event Number 2630

**Condensed Matter Theory Group Seminar****Superconducting Instabilities in Cuprates Mediated by Spin Density Wave Order at Quantum Criticality****Time:**4:30 pm**Place:**5310 Chamberlin**Speaker:**Yuxuan Wang, UW-Madison**Abstract:**I will start with the introduction of the model and its uniqueness near quantum criticality, especially, its distinction with BCS-type theories. I will use a solved example in a specific temperature scale to show how in this case perturbation theory fails to account for the critical temperature of the system. Next I will demonstrate that in another temperature scale the superconducting vertex shows a log^{2}(Λ/T) behavior up to leading contributions, which would seem to give T_{c}~ exp (−1/√*g*),*g*being the coupling. I will then present how this problem again cannot be properly addressed by counting leading contributions in each order of perturbation theory. Theoretical and numerical investigations are then used to show the actual exp (−1/*g*) behavior of the critical temperature. Finally by looking at the full problem, I will talk about the conditions at which each temperature scale takes dominance, and what one can learn from studying the models at these specific temperature scales.- Add this event to your calendar