Jeudi 1 Decembre, 16h
Amphi Howleck, Esc C, 1ème etage
Spin-lattice coupling effects in the iron based superconductors
I. Paul
The newly discovered iron based superconductors with unusually high transition temperatures
exhibit a rich phase diagram that includes structural, magnetic and superconducting transitions.
As such these materials are the latest playgrounds to study how in complex materials di-erent
phases compete, and how this unconventional setting eventually gives rise to superconductivity.
The -rst part of the talk will be a review of this topic. From a theoretical point of view one
of the goals at present is to identify the microscopic interactions that give rise to the rich phase
diagram. This is the motivation to present in the second part of the talk a study of the e-ects of
magneto-elastic couplings between the magnetic and the lattice degrees of freedom. We will argue
that several unusual magneto-structural features of these materials can be understood from this
point of view.