Mapping out the spin fluctuations in Co-doped LaFeAsO single crystals by NMR

Abstract

We determine the phase diagram of LaFe${}_{1-x}$Co${}_x$AsO single crystals by using nuclear magnetic resonance (NMR). Up to a nominal doping of $x=0.03$, it follows the phase diagram for F-doped polycrystals. Above $x=0.03$, the F-doped samples become superconducting, whereas for Co-doping the structural and magnetic transitions can be observed up to $x=0.042$, and superconductivity occurs only for higher doping levels and with reduced transition temperatures. For dopings up to $x=0.056$, we find evidence for short-range magnetic order. By means of relaxation-rate measurements, we map out the magnetic fluctuations that reveal the interplay of nematicity and magnetism. Above the nematic ordering, the spin fluctuations in LaFe${}_{1-x}$Co${}_x$AsO are identical to those in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$, suggesting that nematicity in LaFeAsO is a result of the fluctuating spin density wave as well.

References in corpus (48)

• Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Nematic order in iron superconductors - who is in the driver's seat?
• Theory of Electron Nematic Order in LaOFeAs
• Orbital Fluctuation Mediated Superconductivity in Iron Pnictides: Analysis of Five Orbital Hubbard-Holstein Model
• Ising and Spin orders in Iron-based Superconductors
• Stretched Exponential Relaxation Arising from a Continuous Sum of Exponential Decays
• Anomalous suppression of the orthorhombic distortion in superconducting Ba[Fe(1-x)Cox]2As2
• Ferro-Orbital Order and Strong Magnetic Anisotropy in the Parent Compounds of Iron-Pnictide Superconductors
• Orbital-driven nematicity in FeSe
• Enhancement of superconductivity near a nematic quantum critical point
• Are non-Fermi-liquids stable to Cooper pairing?
• ${}^{75}$As NMR studies of superconducting LaO${}_{0.9}$F${}_{0.1}$FeAs
• Origin of the tetragonal-to-orthorhombic (nematic) phase transition in FeSe: a combined thermodynamic and NMR study
• Contrasting Spin Dynamics Between Underdoped and Overdoped Ba(Fe[1-x]Co[x])2As2
• Commensurate Itinerant Antiferromagnetism in BaFe2As2: 75As-NMR Studies on a Self-Flux Grown Single Crystal
• Orbital Order and Spontaneous Orthorhombicity in Iron Pnictides
• Nematic spin correlations in the tetragonal state of uniaxial strained BaFe2-xNixAs2
• Magnetism, superconductivity, and spontaneous orbital order in iron-based superconductors: who comes first and why?
• Nematicity and magnetism in FeSe and other families of Fe-based superconductors
• NMR Search for the Spin Nematic State in LaFeAsO Single Crystal
• Scaling between magnetic and lattice fluctuations in iron-pnictide superconductors
• Nematic fluctuations and the magneto-structural phase transition in $\mathrm{Ba}(\mathrm{F}{\mathrm{e}}_{1-\mathrm{x}}\mathrm{C}{\mathrm{o}}_{\mathrm{x}}{)}_2\mathrm{A}{\mathrm{s}}_2$
• Nanoscale electronic order in iron pnictides
• Antiferromagnetism of SrFe2As2 studied by Single-Crystal 75As-NMR
• Coexistence of cluster spin glass and superconductivity in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ for $0.060\le x\le 0.071$
• Uniaxial strain control of spin-polarization in multicomponent nematic order of BaFe${}_2$As${}_2$
• Stripe antiferromagnetic correlations in LaFeAsO1-xFx probed by 75As NMR
• Magneto-elastic quantum fluctuations and phase transitions in the iron superconductors
• Pairing instability near a lattice-influenced nematic quantum critical point
• NMR evidence for inhomogeneous glassy behavior driven by nematic fluctuations in iron arsenide superconductors
• Orbital Order and Spin Nematicity in the Tetragonal Phase of Electron-doped Iron-Pnictides NaFe${}_{1-x}$Co${}_x$As
• Progressive slowing down of spin fluctuations in underdoped LaFeAsO${}_{1-x}$F${}_x$
• ${}^{139}$La NMR investigation of the interplay between the lattice, charge, and spin dynamics in charge ordered high $T_c$ cuprate La${}_{1.875}$Ba${}_{0.125}$CuO${}_4$
• Separate tuning of nematicity and spin fluctuations to unravel the origin of superconductivity in FeSe
• Spin-Orbital-Intertwined Nematic State in FeSe
• Unusual disorder effects in superconducting LaFeAs_(1-d)O_0.9F_0.1 as revealed by NMR spectroscopy
• Evolution of the nematic susceptibility in LaFe${}_{1-x}$Co${}_x$AsO
• Singular magnetic anisotropy in the nematic phase of FeSe
• Critical Behavior of the SDW Transition in Underdoped Ba(Fe1-xCox)2As2 (x <=0.05): 75As NMR Investigation
• NMR study of nematic spin fluctuations in a detwinned single crystal of underdoped Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Evidence of unconventional low-frequency dynamics in the normal phase of Ba(Fe1-xRhx)2As2 iron-based supercondutors
• Enhanced anisotropic spin fluctuations below tetragonal-to-orthorhombic transition in LaFeAs(O_{1-x}F_x) probed by ^{75}As and ^{139}La NMR
• Increasing stripe-type fluctuations in $A$Fe${}_2$As${}_2$ ($A$ = K, Rb, Cs) superconductors probed by ${}^{75}$As NMR spectroscopy
• Cu nuclear magnetic resonance study of charge and spin stripe order in La${}_{1.875}$Ba${}_{0.125}$CuO${}_4$
• Nematicity and magnetism in LaFeAsO single crystals probed by ${}^{75}$As nuclear magnetic resonance
• A unified phase diagram of F-doped LaFeAsO by means of NMR and NQR parameters
• Revisiting the phase diagram of LaFe${}_{1-x}$Co${}_x$AsO on single crystals by thermodynamic methods