Directly to content
  1. Publishing |
  2. Search |
  3. Browse |
  4. Recent items rss |
  5. Open Access |
  6. Jur. Issues |
  7. DeutschClear Cookie - decide language by browser settings

Competing Orders in Strongly Correlated Systems - Dirac Materials and Iron-Based Superconductors

Classen, Laura

[thumbnail of dissertation_classen.pdf]
Preview
PDF, English
Download (5MB) | Terms of use

Citation of documents: Please do not cite the URL that is displayed in your browser location input, instead use the DOI, URN or the persistent URL below, as we can guarantee their long-time accessibility.

Abstract

In this work we address the collective phenomena appearing in interacting fermion systems due to the competition of distinct orders at the example of Dirac materials and iron-based superconductors. On the one hand we determine leading ordering tendencies in an unbiased way, when Fermi liquid instabilities are expected simultaneously in the particle-particle and particle-hole channel. In this context we analyze the impact of electron-phonon interactions on the many-body instabilities of electrons on the honeycomb lattice. Furthermore we investigate the interplay between superconductivity, magnetism and orbital order in five-pocket iron-based superconductors including the full orbital composition of low-energy excitations. On the other hand we study how the close proximity of different phases affects the structure of the phase diagram and the nature of transitions, as well as the corresponding quantum multicritical behavior. To this end we consider the semimetal-insulator transitions to an antiferromagnetic and a staggered-density state of low-energy Dirac fermions. To account for the decisive role of interactions and the various degrees of freedom in these models, modern renormalization group techniques are applied.

Document type: Dissertation
Supervisor: Scherer, PD Dr. Michael
Date of thesis defense: 4 November 2016
Date Deposited: 16 Nov 2016 07:42
Date: 2016
Faculties / Institutes: The Faculty of Physics and Astronomy > Institute for Theoretical Physics
DDC-classification: 530 Physics
About | FAQ | Contact | Imprint |
OA-LogoDINI certificate 2013Logo der Open-Archives-Initiative