Abstract

Strongly correlated many-body systems are at the heart of many recent problems in condensed matter physics ranging from high-temperature superconductivity to colossal magnetoresistance. A wealth of analytic tools was developed to tackle the mechanics of these system. Excitations define many important characteristics in many- body systems which can be measured by e. g. angle-resolved photoemission. But due to their complex nature, inherent defects as well as experimental difficulties many open questions remain.

© 2009 IEEE