2018/09/30 by M. A. R. Griffith, M. A. Griffith, M. A. Contínentino +3 · 7 citations
Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Degenerate energy levels #Electron #Ground state #Kondo effect #Kondo insulator #Mathematics #Phase (matter) #Phase diagram #Physics #Quantum mechanics #Rare-earth and actinide compounds #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.99.075109
published in Physical review. B./Physical review. B 99(7) (American Physical Society) · 8 pages, 2 figures
openalex publication_date 2019/02/06 · arxiv created 2019/06/27 · arxiv updated 2019/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We consider the simplest variant of a Kondo insulator where a doublet of localized f electrons hybridizes with spin-degenerate conduction electrons. We analyze the symmetries of f orbitals involved in the hybridization and point out that the effective four-band model of such systems provides further descriptions of clean Kondo insulators; namely the spin texture of the surface states is described by an integer winding number. We discuss general conditions for the appearance of topological nontrivial states and implications for rare-earth-based compounds. As an example, we derive the full phase diagram of tetragonal Kondo insulators. In particular, our findings describe the spin texture in the physically interesting nontrivial topological phase, i.e., when the bandwidth of conduction electrons sets the largest energy scale, and a new weak topological phase appears as a function of the normalized distance between the bands' center.