Correlated phenomena
This is a general category of phenomena in condensed matter systems that cannot be understood from the stand point of non-interacting electron picture. Prominent examples of correlated phenomena include superconductivity and magnetism.
-
Subir Sachdev http://qpt.physics.harvard.edu/publications.html
books
https://www.amazon.com/Fundamentals-Theory-Metals-Abrikosov/dp/0486819019
ntroduction to Modern Solid State Physics - Yuri M. Galperin