The effect of Ca-substitution in La-site on the magnetic properties of La{sub 2}CoMnO{sub 6}

Journal Article · Mon Jul 21 04:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4890321· OSTI ID:22308478

Li, Qiu-hang; Li, Na; Hu, Jian-zhong; Han, Qi; Ma, Qing-shan; Ge, Lei; Xiao, Biao; Xu, Ming-xiang ^[1]

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1. Department of Physics and Key Laboratory of MEMS of the Ministry of Education, Southeast University, Nanjing 210096 (China)

Double perovskite La{sub 2-x}Ca{sub x}CoMnO{sub 6} (x = 0, 0.1, 0.2, 0.5) ceramics samples were synthesized by the standard solid-state reaction method. The crystal structures have been confirmed to be monoclinic perovskite structure with space group of P2{sub 1}/n at room temperature by the powder x-ray diffraction (Cu-Kα). The grains of the samples are relatively dense and distribute in random directions from the scanning electron microscope patterns. Holes are doped into La{sub 2}CoMnO{sub 6} with the substitution of the Ca{sup 2+} ions in La-site, and further lead to the valences of Mn ions and Co ions transforming from Mn{sup 4+} and Co{sup 2+} to Mn{sup 3+} and Co{sup 3+}, respectively. Ferromagnetic coupling of Mn{sup 4+}-O{sup 2–}-Co{sup 2+} and antiferromagnetic coupling of Mn{sup 3+}-O{sup 2–}-Co{sup 3+} are coexistent in La{sub 2-x}Ca{sub x}CoMnO{sub 6} system, which correspond to two transitions existed in field-cooling magnetization versus temperature curves. Curie temperature of La{sub 2-x}Ca{sub x}CoMnO{sub 6} system decreases with the increasing of Ca-substitution amount. The coexistence of different magnetic phases leads to the exchange bias effect.

• OSTI ID: 22308478
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 3 Vol. 116; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANTIFERROMAGNETISM
CALCIUM IONS
CERAMICS
COBALT COMPOUNDS
COBALT IONS
CURIE POINT
DOPED MATERIALS
LANTHANUM COMPOUNDS
MAGNETIC PROPERTIES
MAGNETIZATION
MANGANATES
MANGANESE IONS
MONOCLINIC LATTICES
OXYGEN IONS
PEROVSKITE
SCANNING ELECTRON MICROSCOPY
SPACE GROUPS
TEMPERATURE RANGE 0273-0400 K
X-RAY DIFFRACTION