Study of single impurity Anderson model and dynamical mean field theory based on equation-of-motion method [Elektronische Ressource] / von Qingguo Feng

Study of single impurity Anderson model anddynamical mean eld theory based onequation-of-motion methodDissertationzur Erlangung des Doktorgradesder Naturwissenschaftenvorgelegt beim Fachbereich Physikder Goethe{Universit at Frankfurtin Frankfurt am MainvonQingguo Fengaus Shandong (China)Frankfurt am Main 2009(D30)vom Fachbereich Physik der Goethe{Universit at Frankfurt als Dissertation angenommen.Prufungsk ommission:Prof. Dr. Claudius Gros (Vorsitz)Dr. Harald O. JeschkeProf. Dr. Jens Muller (Protokoll)Prof. Dr. Jochim MaruhnPrufungszeit: 16. November, 2009Dekan: Prof. Dr. Dirk-Hermann RischkeGutachter: Dr. Harald O. Jeschke,Prof. Dr. Claudius Gros,Prof. Dr. Fakher Assaad (Universit at Wurzburg)to my parentsAbstractIn this thesis, we studied the single impurity Anderson model and developed a new and fastimpurity solver for the dynamical mean eld theory (DMFT). Using this new impurity solver,we studied the Hubbard model and periodic Anderson model for various parameters. This workis motivated by the fact that the dynamical mean eld theory is widely used for the studies ofstrongly correlated systems, and the most frequently used methods, e.g. the quantum Monte-Carlomethod (QMC), and the exact digonalization method are much CPU time consuming and usuallylimited by the available computers. Therefore, a fast and reliable impurity solver is needed.