title: Transverse magnetism in uniaxial antiferromagnet UNiGa.
abstract: UNiGa crystallizes in the hexagonal ZrNiAl structure and orders antiferromagnetically below T(N)=39.3 K with the U moments oriented along the c-axis (easy magnetization axis). There are four different antiferromagnetic phases in zero magnetic field and two field induced magnetic phases in UNiGa. For all of them, a strong uniaxial anisotropy is encountered. All the magnetic phases are described by propagation vectors of (0 0 q(i))-type, where q(i) describes the stacking of the ferromagnetic basal planes along the hexagonal c-axis. However, recently (0 0 L)-type Bragg reflections associated with the magnetic ordering have been observed by neutron diffraction. Based on unpolarized and polarized neutron diffraction and non-resonant and resonant synchrotron x-ray scattering experiments combined with polarization analysis we conclude that small amounts of magnetic moments oriented perpendicular to the c-axis exist in UNiGa. Whether these moments reside on Ni atoms outside the U-Ni planes or at interstitial regions could not be determined.
authors.affiliation: Helmholtz-Zentrum Berlin für Materialien und Energie, M-I1, Hahn-Meitner-Platz 1, 14109 Berlin, Germany. prokes@helmholtz-berlin.de
authors.forename: K
authors.initials: K
authors.lastname: Prokeš
authors.forename: R
authors.initials: R
authors.lastname: Feyerherm
authors.forename: E
authors.initials: E
authors.lastname: Dudzik
authors.forename: V
authors.initials: V
authors.lastname: Sechovský
authors.forename: M
authors.initials: M
authors.lastname: Mihalik
mesh_terms: D000497:Alloys / Q000737:chemistry*; D003198:Computer Simulation; D005708:Gallium / Q000737:chemistry*; D008280:Magnetics; D008956:Models, Chemical; D009532:Nickel / Q000737:chemistry*; D014501:Uranium / Q000737:chemistry*
chemical_list: D000497:Alloys; D014501:Uranium; D009532:Nickel; D005708:Gallium