Condensed Matter Seminar: Iron Pnictides and Chalcogenides: doped Mott insulators, itinerant magnets or Hunds metals?

Abstract:

Since the discovery of the iron based superconductors, there has been considerable discussion of the proper theoretical framework for describing these materials and the role played by electronic correlations. 
We will argue that the normal state of these materials are correlated in a way that differs from the Mott Hubbard mechanism, and is controlled  by the Hunds rule coupling. The iron based superconductors are thus Hunds metals, a new class of strongly correlated materials distinct from doped Mott insulators and itinerant magnets. 

In this seminar we will introduce these ideas and review a broad range experimental studies including transport, optical and neutron spectroscopies together with together with LDA+DMFT results support of this picture. 

We will conclude with some comments on the implications for the superconducting state. 

Event Organizer: Prof. Eli Eisenberg