Gap Structure and Symmetry of Fe-based Superconductors
|Date/Time:||Monday, 07 Nov 2011 - Monday, 07 Nov 2011|
|Location:||Physics Hall Room 5|
The new Fe-based superconductors have occasioned considerable excitement be-cause transition temperatures are high, and it is hoped that comparisons to cuprates will lead to new insights into the essential ingredients for high temperature super-conductivity.
I will review what is known about the superconducting state, explaining the basis for the near-consensus that all pnictide materials display spin singlet, orbital s-wave symmetry. Somewhat more controversial are differing reports on gap structure advanced by different experimental probes on different materials, including varying claims of gap nodes or fully gapped behavior. Within the context of a spin fluctuation pairing theory of such systems, this diversity of gap structures, unexpected based on intuition from the high-Tc cuprate superconductors, is easy to understand. High-Tc superconductivity in these unusual multiband materials poses anew, and offers new insight into, the question of how higher temperature superconductivity can be achieved.