A Magnetic Transition Probed by the Ce Ion in Square-Lattice Antiferromagnet CeMnAsO

Abstract

We examined the magnetic properties of the square-lattice antiferromagnets CeMnAsO and LaMnAsO and their solid solutions La1-xCexMnAsO by resistivity, magnetic susceptibility, and heat capacity measurements below room temperature. A first-order phase transition is observed at 34.1 K, below which the ground-state doublet of the Ce ion splits by 3.53 meV. It is likely that Mn moments already ordered above room temperature are reoriented at the transition, as reported for related compounds, such as NdMnAsO and PrMnSbO. This transition generates a large internal magnetic field at the Ce site in spite of the fact that simple Heisenberg interactions should be cancelled out at the Ce site owing to geometrical frustration. The transition takes place at nearly the same temperature with the substitution of La for Ce up to 90%. The Ce moment does not undergo long-range order by itself, but is parasitically induced at the transition, serving as a good probe for detecting the magnetism of Mn spins in a square lattice.

11 pages, 5 figures, to be published in J. Phys. Soc. Jpn

References in corpus (12)

• Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO${}_{1-x}$F${}_x$FeAs
• Structural and magnetic phase diagram of CeFeAsO1-xFx and its relationship to high-temperature superconductivity
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Interplay of Rare Earth and Iron magnetism in RFeAsO with R = La, Ce, Pr, and Sm: A muon spin relaxation study and symmetry analysis
• Electronic structure and Magnetism in BaMn${}_2$As${}_2$ and BaMn${}_2$Sb${}_2$
• CeFePO: A Heavy Fermion Metal with Ferromagnetic Correlations
• A variable temperature study of the crystal and magnetic structures of the giant magnetoresistant materials LnMnAsO (Ln = La, Nd)
• The crystalline electric field as a probe for long range antiferromagnetic order and superconductivity in CeFeAsO${}_{1-x}$F${}_x$
• Local moment versus Kondo behavior of the 4f-electrons in rare-earth iron oxypnictides
• Nd induced Mn spin-reorientation transition in NdMnAsO
• Interplay between Fe and Nd magnetism in NdFeAsO single crystals
• Local moments and symmetry breaking in metallic PrMnSbO

Cited by in corpus (9)

• Short- and long-range magnetic order in LaMnAsO
• The magnetic and electronic properties of Oxyselenides - influence of transition metal ions and lanthanides
• Spin reorientation and Ce-Mn coupling in antiferromagnetic oxypnictide CeMnAsO
• Insulator-to-metal transition and large thermoelectric effect in La${}_{1-x}$Sr${}_x$MnAsO
• Magnetism of the Fe${}^{2+}$ and Ce${}^{3+}$ sublattices in Ce${}_2$O${}_2$FeSe${}_2$: a combined neutron powder diffraction, inelastic neutron scattering and density functional study
• Absence of Colossal Magnetoresistance in the Oxypnictide PrMnAsO0.95F0.05
• Spin Dynamics in the Antiferromagnetic Oxypnictides and Fluoropnictides: LaMnAsO, LaMnSbO, and BaMnAsF
• Competing magnetic phases and field-induced dynamics in DyRuAsO
• Crystal field excitations and magnons: their roles in oxyselenides Pr2O2M2OSe2 (M = Mn, Fe)