The poisoning effect of Mn in LaFe(1-x)Mn(x)AsO(0.89)F(0.11): unveiling a quantum critical point in the phase diagram of iron-based superconductors

Abstract

A superconducting-to-magnetic transition is reported for LaFe${}_{1-x}$Mn${}_x$AsO${}_{0.89}$F${}_{0.11}$ where a per thousand amount of Mn impurities is dispersed. By employing local spectroscopic techniques like muon spin rotation (muSR) and nuclear quadrupole resonance (NQR) on compounds with Mn contents ranging from x=0.025% to x=0.75%, we find that the electronic properties are extremely sensitive to the Mn impurities. In fact, a small amount of Mn as low as 0.2% suppresses superconductivity completely. Static magnetism, involving the FeAs planes, is observed to arise for x > 0.1% and becomes further enhanced upon increasing Mn substitution. Also a progressive increase of low energy spin fluctuations, leading to an enhancement of the NQR spin-lattice relaxation rate 1/T1, is observed upon Mn substitution. The analysis of 1/T1 for the sample closest to the the crossover between superconductivity and magnetism (x = 0.2%) points towards the presence of an antiferromagnetic quantum critical point around that doping level.

11 pages, 10 figures

References in corpus (12)

• The electronic phase diagram of the LaO1-xFxFeAs superconductor
• Field and Temperature Dependence of the Superfluid Density in LaO_{1-x}F_xFeAs Superconductors: A Muon Spin Relaxation Study
• Interplay of Rare Earth and Iron magnetism in RFeAsO with R = La, Ce, Pr, and Sm: A muon spin relaxation study and symmetry analysis
• High-Field Pauli-Limiting Behavior and Strongly Enhanced Upper Critical Magnetic Fields near the Transition Temperature of an Arsenic-Deficient LaO_0.9F_0.1FeAs_(1-δ) Superconductor
• MuSR studies of RE(O,F)FeAs (RE = La, Nd, Ce) and LaOFeP systems: possible incommensurate/stripe magnetism and superfluid density
• Suppression of superconductivity by Neel-type magnetic fluctuations in the iron pnictides
• Electronic properties of LaOFFeAs in the normal state probed by NMR/NQR
• Relationship between Superconductivity and Antiferromagnetism in LaFe(As${}_{1-x}$P${}_x$)O Revealed by ${}^{31}$P-NMR
• Coupling between 4f and itinerant electrons in SmFeAsO1-xFx (0.15 < x < 0.2) superconductors: an NMR study
• The onset of magnetism peaked around x=1/4 in optimally electron-doped LnFe(1-x)Ru(x)AsO(1-y)F(y) (Ln = La, Nd or Sm) superconductors
• Non-magnetic pair-breaking effect on La(Fe_{1-x}Zn_{x})AsO_{0.85} studied by NMR and NQR
• 75As-NMR Studies of LaFeAsO1-xFx for Various x Values

Cited by in corpus (21)

• Using Gap Symmetry and Structure to Reveal the Pairing Mechanism in Fe-based Superconductors
• Spin fluctuations in iron pnictides and chalcogenides: From antiferromagnetism to superconductivity
• The phase diagrams of iron-based superconductors: theory and experiments
• Unconventional disorder effects in correlated superconductors
• Superconductivity emerging from an electronic phase separation in the charge ordered phase of RbFe${}_2$As${}_2$
• Experimental Evidences for Static Charge Density Waves in Iron Oxy-pnictides
• Iron-based superconductors: tales from the nuclei
• Fast recovery of the stripe magnetic order by Mn/Fe substitution in F-doped LaFeAsO superconductors
• Spatial competition of the ground states in 1111 iron pnictides
• Competing superconducting and magnetic order parameters and field-induced magnetism in electron doped Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Role of magnetic dopants in the phase diagram of Sm1111 pnictides: The Mn case
• Competing effects of Mn and Y doping on the low-energy excitations and phase diagram of La${}_{1-y}$Y${}_y$Fe${}_{1-x}$Mn${}_x$AsO${}_{0.89}$F${}_{0.11}$ iron-based superconductors
• Miscibility gap and possible intrinsic Griffiths phase in Sr(Fe1-xMnx)2As2 crystals grown by transitional metal arsenide flux
• Impurity effects on spin dynamics in magnetic and superconducting iron pnictides and chalcogenides
• Evolution of Magnetic Double Helix and Quantum Criticality near a Dome of Superconductivity in CrAs
• Fast recovery of the pristine magnetic and structural phases in superconducting LaFeAsO${}_{0.89}$F${}_{0.11}$ by Mn/Fe substitution
• Magnetic disorder and gap symmetry in optimally electron doped Sr(Fe, Co)${}_2$As${}_2$ superconductor
• Antiferromagnetic order and its interplay with superconductivity in CaK(Fe${}_{1-x}$Mn${}_x$)${}_4$As${}_4$
• Effect of Mn Substitution on Superconductivity in PrFeAs(O,F): Role of Magnetic Impurities
• Tuning Superconductivity by Isovalent Antimony Substitution in PrFeAs(O,F)
• Nematicity in LaFeAsO single crystals studied by elastoresistance, high-resolution thermal expansion and shear-modulus measurements