First order magnetic transition in single crystal CaFe${}_2$As${}_2$ detected by ${}^{75}$As NMR

Abstract

We report ${}^{75}$As Nuclear Magnetic Resonance data in a single crystal of CaFe${}_2$As${}_2$. The Knight shift, electric field gradient, and spin-lattice relaxation rate are strongly temperature dependent in the paramagnetic state, and change discontinuously at the structural transition temperature, $T_S=T_N=167$ K. Immediately below, the NMR spectra reveal an internal field at the As site associated with the presence of a commensurate magnetic order. These results indicate that the structural and magnetic transitions in CaFe${}_2$As${}_2$ are first order and strongly coupled, and that the electron density in the FeAs plane is highly sensitive to the out-of-plane structure.

In Fig. 2, we incorrectly assigned AFM lines and quadrupole satellites. Fig.3 and the numbers in the text were corrected accordingly. This mistake has no affect on our main conclusion however

References in corpus (27)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• 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
• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• Superconductivity up to 37 K in (A1-xSrx)Fe2As2 with A=K and Cs
• Superconductivity in iron-based F-doped layered quaternary compound Nd[O1-xFx]FeAs
• Pressure induced superconductivity in CaFe${}_2$As${}_2$
• Superconductivity up to 29 K in SrFe2As2 and BaFe2As2 at high pressures
• Anisotropic thermodynamic and transport properties of single crystalline (Ba${}_{1-x}$K${}_x$)Fe${}_2$As${}_2$ (x = 0 and 0.45)
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• First order structural phase transition in CaFe${}_2$As${}_2$
• ${}^{75}$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
• Spin-singlet superconductivity with multiple gaps in PrO0.89F0.11FeAs
• Spin and Lattice Structure of Single Crystal SrFe2As2
• Antiferromagnetic transition in EuFe${}_2$As${}_2$: A possible parent compound for superconductors
• Superconductivity at 53.5 K in GdFeAsO1-delta
• Different resistivity response to spin density wave and superconductivity at 20 K in $C{a}_{1-x}N{a}_{x}F{e}_{2}A{s}_2$
• Synthesis and Properties of CaFe${}_2$As${}_2$ Single Crystals
• Electrical Resistivity and Specific Heat of EuFe2As2 Single Crystals: Magnetic homologue of SrFe2As2
• Pressure-induced superconductivity in single crystal CaFe2As2
• Strong coupling between magnetic and structural order parameters in SrFe2As2
• Anisotropic three-dimensional magnetism in CaFe2As2
• Specific heat of the iron-based high-$T_c$ superconductor SmO${}_{1-x}$F${}_x$FeAs
• Columnar magnetic structure coupled with orthorhombic distortion in the antiferromagnetic iron arsenide SrFe${}_2$As${}_2$
• Spin Dynamics in Iron-based Layered Superconductor (La_{0.87}Ca_{0.13})FePO Revealed by ^{31}P and ^{139}La NMR Studies
• Microscopic study of the effect of impurities on the first order spin density wave transition in BaFe${}_2$As${}_2$

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• Presure-Induced Superconducting State of Antiferromagnetic CaFe${}_2$As${}_2$
• NMR investigation of superconductivity and antiferromagnetism in CaFe${}_2$As${}_2$ under pressure
• Low energy spin dynamics in the antiferromagnetic phase of CaFe2As2
• Antiphase magnetic boundaries in iron-based superconductors: A first-principle density-functional theory study