Interplay between Fe 3d and Ce 4f magnetism and Kondo interaction in CeFeAs_{1-x}P_{x}O probed by ^{75}As and ^{31}P NMR

Abstract

A detailed ${}^{31}$P (I=1/2) and ${}^{75}$As (I=3/2) NMR study on polycrystalline CeFeAs${}_{1-x}$P${}_x$O alloys is presented. The magnetism of CeFeAsO changes drastically upon P substitution on the As site. CeFePO is a heavy fermion system without long range order whereas CeFeAsO exhibits a Fe-3$d$ SDW type of ordering accompanied by a structural transition from tetragonal ($TT$) to orthorhombic ($OT$) structure. Furthermore Ce-4$f^1$ orders antiferromagnetically (AFM) at low temperature. At the critical concentration where the Fe-magnetism is diminished the Ce-Ce interaction changes to a ferromagnetic (FM) type of ordering. Three representative samples of the CeFeAs${}_{1-x}$P${}_x$O ($x$=0.05, 0.3 and 0.9) series are systematically investigated. 1) For the $x$=0.05 alloy a drastic change of the line width at 130 K indicates the AFM-SDW type of ordering of Fe and the structural change from $TT$ to $OT$ phase. The line width roughly measures the internal field in the ordered state and the transition is most likely first order. The small and nearly constant shift for ${}^{31}$P and ${}^{75}$As suggests the presence of competing hyperfine interactions between the nuclear spins and the 4$f$ and 3$d$ ions of Ce and Fe. 2) For the $x$=0.3 alloy, evolution of the Fe-SDW type order takes place at around 70 K corroborating the results of bulk measurement and $\mu SR$. Here we found strong evidence for phase separation of paramagnetic and magnetic SDW phases. 3) In contrast to heavy fermion CeFePO for the $x$=0.9 alloy a phase transition is found at 2 K. The field-dependent NMR shift gives strong evidence of FM ordering. Above the ordering the spin lattice relaxation rate ${}^{31}$(1/T${}_1$) shows unconventional, non-Korringa like behaviour which indicates a complex interplay of Kondo and FM fluctuations.

10 (+) pages, 11 figures, Accepted in Journal of Physics condensed Matter

References in corpus (23)

• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• 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
• Superconductivity at 52 K in iron-based F-doped layered quaternary compound Pr[O1-xFx]FeAs
• Evolution from Itinerant Antiferromagnet to Unconventional Superconductor with Fluorine Doping in La(O_{1-x}F_{x})FeAs Revealed by ^{75}As and ^{139}La Nuclear Magnetic Resonance
• ${}^{75}$As NMR studies of superconducting LaO${}_{0.9}$F${}_{0.1}$FeAs
• Commensurate Itinerant Antiferromagnetism in BaFe2As2: 75As-NMR Studies on a Self-Flux Grown Single Crystal
• Iron pnictides as a new setting for quantum criticality
• Interplay of Rare Earth and Iron magnetism in RFeAsO with R = La, Ce, Pr, and Sm: A muon spin relaxation study and symmetry analysis
• CeRuPO: A rare example of a Ferromagnetic Kondo lattice
• High pressure synthesis of late rare earth RFeAs(O,F) superconductors; R = Tb and Dy
• CeFePO: A Heavy Fermion Metal with Ferromagnetic Correlations
• Relevance of ferromagnetic correlations for the Electron Spin Resonance in Kondo lattice systems
• Lattice distortion and magnetic quantum phase transition in CeFeAs(1-x)P(x)O
• Phase diagram of CeFeAs${}_{1-x}$P${}_x$O obtained from electric resistivity, magnetization, and specific heat measurements
• First order magnetic transition in single crystal CaFe${}_2$As${}_2$ detected by ${}^{75}$As NMR
• The crystalline electric field as a probe for long range antiferromagnetic order and superconductivity in CeFeAsO${}_{1-x}$F${}_x$
• Rare earth magnetism in CeFeAsO: A single crystal study
• NMR investigation of superconductivity and antiferromagnetism in CaFe${}_2$As${}_2$ under pressure
• Single crystal growth and anisotropy of CeRuPO
• Influence of the Nd $4f$ states on the magnetic behavior and the electric field gradient of the oxypnictides superconductors NdFeAsO${}_{1-x}$F${}_x$
• 75As NMR study of the ternary iron arsenide BaFe2As2
• 75As-NMR studies on La FeAsO1-xFx (x=0.14) under a pressure of 3GPa

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• Multigap superconductivity in locally non-centrosymmetric SrPtAs: An As nuclear quadrupole resonance investigation