2017/06/30 by Debanjan Chowdhury, Inti Sodemann, T. Senthil · 2 citations
Physics and Astronomy · #Exciton #Fermi Gamma-ray Space Telescope #Fermi level #Fermi surface #Gapless playback #Insulator (electricity) #Paramagnetism #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Superconductivity in MgB2 and Alloys #Valence (chemistry) #cond-mat.str-el
paper · pdf · doi:10.1038/s41467-018-04163-2
published as Nature Communications 9, 1766 (2018) · Final published version
openalex created_date 2017/06/09 · openalex publication_date 2018/04/26 · arxiv created 2018/05/07 · arxiv updated 2018/05/08 · openalex updated_date 2026/08/05
Abstract Samarium hexaboride is a classic three-dimensional mixed valence system with a high-temperature metallic phase that evolves into a paramagnetic charge insulator below 40 K. A number of recent experiments have suggested the possibility that the low-temperature insulating bulk hosts electrically neutral gapless fermionic excitations. Here we show that a possible ground state of strongly correlated mixed valence insulators—a composite exciton Fermi liquid—hosts a three dimensional Fermi surface of a neutral fermion, that we name the “composite exciton.” We describe the mechanism responsible for the formation of such excitons, discuss the phenomenology of the composite exciton Fermi liquids and make comparison to experiments in SmB 6 .