2019/08/13 by R. D. Johnson, Roger D. Johnson, Ineke Broeders +10
Chemistry · Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Charge (physics) #Chemistry #Condensed matter physics #Crystal structure #Crystallography #Ion #Isostructural #Magnetic and transport properties of perovskites and related materials #Magnetism #Materials science #Mott insulator #Octahedron #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.100.214113
published as Phys. Rev. B 100, 214113 (2019)
arxiv created 2019/08/13 · openalex created_date 2019/08/22 · openalex publication_date 2019/12/18 · arxiv updated 2019/12/25 · openalex updated_date 2026/08/06
We report structural studies of the spin-orbit Mott insulator family KxIryO2, with triangular layers of edge-sharing IrO6 octahedra bonded by potassium ions. The potassium content acts as a chemical tuning parameter to control the amount of charge in the Ir-O layers. Unlike the isostructural families with Ir replaced by Co or Rh (y=1), which are metallic over a range of potassium compositions x, we instead find insulating behavior with charge neutrality achieved via iridium vacancies, which order in a honeycomb supercell above a critical composition xc. By performing density functional theory calculations we attribute the observed behavior to a subtle interplay of crystal-field environment, local electronic correlations, and strong spin-orbit interaction at the Ir4+ sites, making this structural family a candidate to display Kitaev magnetism in the experimentally unexplored regime that interpolates between triangular and honeycomb structures.