Department of Physics
Condensed Matter Seminar

There is growing evidence that the newly discovered high-Tc superconductivity in ferropnictides is intimately related to their unique magnetic properties. In the first part of the talk I will discuss the electronic structure of ferropnictides as it emerges from the density functional calculations, and will show that this electronic structure strongly favors a new unconventional superconducting state with an s-wave angular dependence of the gap, but with a sigh-changing order parameter. I will also discuss experimental evidence for and against this state. In the second part of the talk I will argue for strong incipient antiferromagnetism in both parent and superconducting ferropnictides and discuss several hypotheses about why this string magnetism has not been observed, or observed at a much weaker level, in the available experiments.