Materials with Strong Electronic Correlations:
Solid-state Physics from an Atomic Viewpoint

Antoine Georges
Ecole Polytechnique

From copper-oxide superconductors to rare-earth based environmentally-
friendly pigments, materials with strong electronic correlations have 
focused enormous attention over the last two decades.  Solid-state 
chemistry, new elaboration techniques and improved experimental probes are 
constantly providing us with examples of new materials with surprising 
electronic properties. In this colloquium, I will emphasize that the classic 
paradigm of solid-state physics, in which electrons form a gas of wave-like 
quasiparticles, must be seriously revised for these materials. Instead, a 
description in which atomic-like excitations also retain a well-defined 
meaning in the solid state is in order. The "dynamical mean-field theory" 
of strong electronic correlations has been forged in order to achieve this 
goal. In an inter-disciplinary endeavor bringing together the many-body and 
electronic structure communities, this approach has been combined with 
first-principles calculations, so that theory can now address the properties 
of specific materials in a realistic setting.