Events at Physics

<< Summer 2011 Fall 2011 Spring 2012 >>
Subscribe your calendar or receive email announcements of events
Condensed Matter Theory Group Seminar
Spin resonance in Fe-based superconductors
Date: Monday, November 21st
Time: 4:30 pm
Place: 5310 Chamberlin
Speaker: Saurabh Maiti, UW-Madison
Abstract: Fe-based superconductors(FeSCs) and cuprates are often held as prime candidates for study that can lead to the understanding of the unconventional high Tc superconductivity. In this talk, I will briefly mention the motivation behind looking for spin resonance in unconventional superconductors. I will mention some the similarities and differences that are seen in experiments in these two family of compounds. Unlike in the cuprates where people agree on the d-wave symmetry, FeSCs are much more interesting. Different symmetries and structures are possible for the gap structure in these materials. Observation of a spin resonance indicates presence of on order parameter that needs to flip its sign in some parts of the Fermi-surface. Experiments in FeSC actually see a relatively broad peak (unlike in cuprates) and this has been argued by some groups to be due to a 'sign preserving' order parameter contrary to the popular 'sign-flipping' order parameter in FeSCs. In this talk I will present our resolution of the conflict and explain how the experimental observations can be understood by accounting for nodes in the gap, impurity scattering and Fermi-surface geometry.
Host: Perkins
Add this event to your calendar