title: Itinerant ferromagnetism in the As 4p conduction band of Ba_{0.6}K_{0.4}Mn_{2}As_{2} identified by X-ray magnetic circular dichroism.
abstract: X-ray magnetic circular dichroism (XMCD) measurements on single-crystal and powder samples of Ba_{0.6}K_{0.4}Mn_{2}As_{2} show that the ferromagnetism below T_{C}≈100  K arises in the As 4p conduction band. No XMCD signal is observed at the Mn x-ray absorption edges. Below T_{C}, however, a clear XMCD signal is found at the As K edge which increases with decreasing temperature. The XMCD signal is absent in data taken with the beam directed parallel to the crystallographic c axis indicating that the orbital magnetic moment lies in the basal plane of the tetragonal lattice. These results show that the previously reported itinerant ferromagnetism is associated with the As 4p conduction band and that distinct local-moment antiferromagnetism and itinerant ferromagnetism with perpendicular easy axes coexist in this compound at low temperature.
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: B G
authors.initials: BG
authors.lastname: Ueland
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Pandey
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: A
authors.initials: A
authors.lastname: Sapkota
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: Y
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: R A
authors.initials: RA
authors.lastname: Rosenberg
authors.affiliation: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Lang
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: B N
authors.initials: BN
authors.lastname: Harmon
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Johnston
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: A
authors.initials: A
authors.lastname: Kreyssig
authors.affiliation: Ames Laboratory, U.S. Department of Energy, Iowa State University, Ames, Iowa 50011, USA.|Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
authors.forename: A I
authors.initials: AI
authors.lastname: Goldman