TY - JOUR
T1 - Crystallographic structure and magnetic ordering in CaMn 1-xRuxO3 (x ≤ 0.40) manganites
T2 - Neutron diffraction, ac susceptibility, and electron magnetic resonance studies
AU - Shames, Alexander
AU - Rosenberg, Evgeny
AU - Martin, C.
AU - Maignan, A.
AU - Raveau, B.
AU - André, G.
AU - Gorodetsky, Gad
N1 - Funding Information:
A.I.Sh., E.R. and G.G. thank the Israeli Science Foundation administered by the Israel Academy of Sciences and Humanities for the support of this work (Grant No. 209/01). The authors also thank Professor G. Jung for fruitful discussions.
PY - 2004/10/1
Y1 - 2004/10/1
N2 - Neuron powder diffraction (NPD), ac susceptibility and electron magnetic resonance (EMR) techniques were employed for studying the crystallographic structure and magnetic ordering in CaMn1-xRuxO3 (x ≤ 0.40) manganite system. It is shown that CaMn1-xRu xO3 crystallizes in an orthorhombic Pnma perovskite structure within the temperature interval 1.5 ≤ T ≤ 300 K independently on the level of Ru-doping (x). It means that the changes of the magnetic ordering in this system are solely determined by doping of Mn sites with Ru in parent CaMnO3 compound. The NPD data show also that the long-ranged ferromagnetic (FM) ordering is developed in x ≥ 0.10 compounds within antiferromagnetically (AFM) ordered matrix. The volume of this FM phase increases with x at the expense of the AFM one. The ac susceptibility (χ) demonstrates broadened peaks on χ(T) curves for x=0.10, 0.15 samples and characteristic two-peak shape for x=0.40 compound. The frequency dependence of χ(T) curves is also observed for x ≥ 0.10 compounds. The complementary data of EMR indicate, in addition, the complex character of FM ordering, i.e., appearance of some nonequivalent FM phases, differ on its Curie temperatures and magnetocrystalline anisotropies in x ≥ 0.15 samples. The best description of all these results could be done in the frame of the model of phase separated FM+AFM ground state developing in the considered CaMn1-xRu xO3 system for Ru concentrations x ≥ 0.10.
AB - Neuron powder diffraction (NPD), ac susceptibility and electron magnetic resonance (EMR) techniques were employed for studying the crystallographic structure and magnetic ordering in CaMn1-xRuxO3 (x ≤ 0.40) manganite system. It is shown that CaMn1-xRu xO3 crystallizes in an orthorhombic Pnma perovskite structure within the temperature interval 1.5 ≤ T ≤ 300 K independently on the level of Ru-doping (x). It means that the changes of the magnetic ordering in this system are solely determined by doping of Mn sites with Ru in parent CaMnO3 compound. The NPD data show also that the long-ranged ferromagnetic (FM) ordering is developed in x ≥ 0.10 compounds within antiferromagnetically (AFM) ordered matrix. The volume of this FM phase increases with x at the expense of the AFM one. The ac susceptibility (χ) demonstrates broadened peaks on χ(T) curves for x=0.10, 0.15 samples and characteristic two-peak shape for x=0.40 compound. The frequency dependence of χ(T) curves is also observed for x ≥ 0.10 compounds. The complementary data of EMR indicate, in addition, the complex character of FM ordering, i.e., appearance of some nonequivalent FM phases, differ on its Curie temperatures and magnetocrystalline anisotropies in x ≥ 0.15 samples. The best description of all these results could be done in the frame of the model of phase separated FM+AFM ground state developing in the considered CaMn1-xRu xO3 system for Ru concentrations x ≥ 0.10.
UR - http://www.scopus.com/inward/record.url?scp=45849154764&partnerID=8YFLogxK
U2 - 10.1103/PhysRevB.70.134433
DO - 10.1103/PhysRevB.70.134433
M3 - Article
AN - SCOPUS:45849154764
SN - 0163-1829
VL - 70
SP - 134433-1-134433-10
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 13
M1 - 134433
ER -