title: A Combined Functional Renormalization and Mean-Field Study of Competing Orders in the Two-Dimensional Hubbard Model
creator: Veschgini, Kambis
subject: 500
subject: 500 Natural sciences and mathematics
subject: 530
subject: 530 Physics
description: The primary subject of this thesis is the two-dimensional Hubbard model. Using the functional renormalization Group in static approximation we will present the phase diagram of the 2D-Hubbard model and refine it by including frequency dependencies and full self-energy effects. The focus will fall on the vicinity of the quantum critical point, where the system shows a non-Fermi-liquid-like behavior. In mean-field calculations, we show that the frequency dependence of the self-energy has a substantial impact on the ground state. Furthermore, we investigate the relation between the density-density interaction and the quasiparticle lifetime. During the course of our study, we will develop a saddle-point formulation of Schwinger-Dyson equations and present a new renormalization group scheme which is valid for all fermionic systems.
date: 2017
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/22476/1/VESCHGINI_THESIS_PDFA.pdf
identifier: DOI:10.11588/heidok.00022476
identifier: urn:nbn:de:bsz:16-heidok-224763
identifier:   Veschgini, Kambis  (2017) A Combined Functional Renormalization and Mean-Field Study of Competing Orders in the Two-Dimensional Hubbard Model.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/22476/
rights: info:eu-repo/semantics/openAccess
rights: http://archiv.ub.uni-heidelberg.de/volltextserver/help/license_urhg.html
language: eng