2019/11/30 by Jing-Rong Wang, Wei Li, Changjin Zhang +1
Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Fermion #Geometry #Line (geometry) #Mathematics #Physics #Physics of Superconductivity and Magnetism #Quadratic equation #Quantum mechanics #Topological Materials and Phenomena #cond-mat.mtrl-sci #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.102.085132
published as Phys. Rev. B 102, 085132 (2020) · 19 pages, 10 figures
openalex created_date 2019/12/05 · openalex publication_date 2020/08/14 · arxiv created 2021/02/18 · arxiv updated 2021/02/19 · openalex updated_date 2026/08/05
Influence of short-range four-fermion interactions on quadratic and cubic nodal-line fermion systems is studied by renormalization group theory. It is found that arbitrarily weak four-fermion interaction could drive quadratic or cubic nodal-line fermion system to a new phase. According to the initial conditions and value of fermion flavor, the system may appear three kinds of instabilities. First, quadratic or cubic nodal line is split into conventional nodal lines, thus the system becomes nodal-line semimetal. Second, finite excitonic gap is generated, and the system becomes an excitonic insulator. Third, the system is driven into superconducting phase. Thus quadratic and cubic nodal line fermion systems are rare strong correlated fermion systems in three dimensions under the influence of four-fermion interactions. These theoretical results may be verified in the candidates for quadratic and cubic nodal-line fermion systems.