2013/04/16 by Kok Wee Song, Yung-Ching Liang, Hokiat Lim +1 · 4 citations
Materials Science · Physics and Astronomy · #Classical mechanics #Condensed matter physics #Electron #Fermi liquid theory #Ground state #Instability #Iron-based superconductors research #Isotropy #Lattice (music) #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Quartic function #Rare-earth and actinide compounds #Square lattice #Translational symmetry #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.88.054501
published in Physical Review B 88(5) (American Physical Society) · 9 pages, 2 figures
arxiv created 2013/04/16 · openalex publication_date 2013/08/02 · arxiv updated 2013/08/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
In this paper, instabilities of the isotropic metallic phase in iron pnictides are investigated. The relevant quartic fermionic interaction terms in the model are identified using phase space arguments. Using the functional integral formalism, a Hubbard-Stratonovich transformation is used to decouple these quartic terms. This procedure introduces several bosonic fields which describe the low-energy collective modes of the system. By studying the behavior of these collective modes, a possible instability is found in the forward scattering channel of the isotropic phase driven by magnetic fluctuations. Using mean field analysis, we obtain a static and homogeneous ground state. This ground state is metallic, but the electron Fermi pockets are distorted unequally at different pockets in momentum space. This results in a desirable nematic ordering which breaks the lattice C4 symmetry but preserves translational symmetry and may explain several experimental observations.