2019/11/15 by Martin Sundermann, Sundermann, Martin
Physics and Astronomy · #Advanced Chemical Physics Studies #FOS: Physical sciences #Nuclear Physics and Applications #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el) #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.1911.06901
openalex publication_date 2019/11/15 · openalex created_date 2022/07/26 · openalex updated_date 2026/07/28
Strongly correlated materials are characterized by the presence of\nelectron-electron interactions in their electronic structure. They often have\nremarkable properties and transitions between competing phases of very\ndifferent electronic and magnetic order. This thesis focuses on strongly\ncorrelated f-electron compounds containing Ce, Sm, and U. These materials\nexhibit a so-called heavy-fermion or Kondo-lattice behavior. They can become\ninsulating due to hybridization effects (Kondo-insulator) or develop multipolar\n(hidden) order. Kondo insulators have recently been discussed in the context of\nstrongly correlated topological insulators. This new aspect caused an enormous\nactivity in the field of Kondo insulators, theoretically as well as\nexperimentally. Multipolar order as well as the formation of a Kondo insulating\nstate strongly depend on the symmetry of the f states involved. Also the\ncharacter of the surface states in a topological insulator is determined by the\nproperties of the bulk states. Therefore the scope of this thesis has been to\nunveil the underlying symmetries of the bulk f states. Here the compounds\nCeB6, UO2, and URu2Si2, which exhibit multipolar order, as well as\nthe Kondo insulators (semimetals) SmB6 and CeRu4Sn6 have been studied.\n