2008/06/10 by Debabrata Parihari, N. S. Vidhyadhiraja, David E. Logan · 6 citations
Physics and Astronomy · #Anderson impurity model #Condensed matter physics #Density of states #Electron #Field (mathematics) #Kondo effect #Kondo insulator #Magnetic field #Physics #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Quantum mechanics #Rare-earth and actinide compounds #Zeeman effect #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.78.035128
published in Physical Review B 78(3) (American Physical Society) · 8 pages, 8 figures
arxiv created 2008/06/10 · openalex publication_date 2008/07/28 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Magnetic-field effects in Kondo insulators are studied theoretically, using a local-moment approach to the periodic Anderson model within the framework of dynamical mean-field theory. Our main focus is on field-induced changes in single-particle dynamics and the associated hybridization gap in the density of states. Particular emphasis is given to the strongly correlated regime, where the dynamics is found to exhibit universal scaling in terms of a field-dependent low-energy coherence scale. Although the bare applied field is globally uniform, the effective fields experienced by the conduction electrons and the f electrons differ because of correlation effects. A continuous insulator-metal transition is found to occur on increasing the applied field, closure of the hybridization gap reflecting competition between Zeeman splitting, and screening of the f-electron local moments. For intermediate interaction strengths, the hybridization gap depends nonlinearly on the applied field, while in strong coupling its field dependence is found to be linear. For the classic Kondo insulator YbB12, good agreement is found upon direct comparison of the field evolution of the experimental transport gap with the theoretical hybridization gap in the density of states.