title: Competition between heavy fermion and Kondo interaction in isoelectronic A-site-ordered perovskites.
abstract: With current research efforts shifting towards the 4d and 5d transition metal oxides, understanding the evolution of the electronic and magnetic structure as one moves away from 3d materials is of critical importance. Here we perform X-ray spectroscopy and electronic structure calculations on A-site-ordered perovskites with Cu in the A-site and the B-sites descending along the ninth group of the periodic table to elucidate the emerging properties as d-orbitals change from partially filled 3d to 4d to 5d. The results show that when descending from Co to Ir, the charge transfers from the cuprate-like Zhang-Rice state on Cu to the t(2g) orbital of the B site. As the Cu d-orbital occupation approaches the Cu(2+) limit, a mixed valence state in CaCu(3)Rh(4)O(12) and heavy fermion state in CaCu(3)Ir(4)O(12) are obtained. The investigated d-electron compounds are mapped onto the Doniach phase diagram of the competing RKKY and Kondo interactions developed for the f-electron systems.
authors.affiliation: Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA.
authors.forename: D
authors.initials: D
authors.lastname: Meyers
authors.affiliation: Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA.
authors.forename: S
authors.initials: S
authors.lastname: Middey
authors.affiliation: 1] Beijing National Laboratory for Condensed Matter Physics, and Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China [2] Texas Materials Institute, ETC 9.102, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: J-G
authors.initials: JG
authors.lastname: Cheng
authors.affiliation: Department of Condensed Matter Physics and Materials Science, S.N.Bose National Centre for Basic Sciences, Kolkata 700098, India.
authors.forename: Swarnakamal
authors.initials: S
authors.lastname: Mukherjee
authors.affiliation: Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Gray
authors.affiliation: Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Texas Materials Institute, ETC 9.102, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: J-S
authors.initials: JS
authors.lastname: Zhou
authors.affiliation: Texas Materials Institute, ETC 9.102, University of Texas at Austin, Austin, Texas 78712, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Goodenough
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: Yongseong
authors.initials: Y
authors.lastname: Choi
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: D
authors.initials: D
authors.lastname: Haskel
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Freeland
authors.affiliation: Department of Condensed Matter Physics and Materials Science, S.N.Bose National Centre for Basic Sciences, Kolkata 700098, India.
authors.forename: T
authors.initials: T
authors.lastname: Saha-Dasgupta
authors.affiliation: Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701, USA.
authors.forename: J
authors.initials: J
authors.lastname: Chakhalian