日 時： 2013年4月5日（金）15:00～16:30
場 所： 工学部6号館3階セミナー室A/D
講 師： Prof. Antoine Georges（College de France and Ecole Polytechnique, Paris）
題 目： “Strong correlations from Hund’s rule coupling”
The proximity of a Mott insulating state (“Mottness”) is responsible for strong correlations in a number of materials, especially oxides of 3d transition metals. In this talk, I will emphasize that the Hund’s rule coupling induces strong correlation effects in materials which are not close to a Mott insulator. This is especially relevant for oxides of 4d transition metals such as ruthenates, and also for iron-based superconductors. The Hund’s rule coupling will be shown to have antagonistic (“Janus-faced”) effects on the Mott gap and on the quasiparticle coherence scale. For Hund’s correlated materials, the self-consistent embedded-atom construction at the heart of Dynamical Mean-Field Theory proves to be especially meaningful.
L.de’ Medici, J.Mravlje and A.Georges Phys. Rev. Lett. 107, 256401 (2011);
A.Georges, L. de’Medici and J. Mravlje. Annual Reviews of Condensed Matter
Physics, Vol.4 (2013) arXiv:1207.3033