Field and Temperature Dependence of the Superfluid Density in LaO_{1-x}F_xFeAs Superconductors: A Muon Spin Relaxation Study

Abstract

We present zero field and transverse field \muSR experiments on the recently discovered electron doped Fe-based superconductor LaO_{1-x}F_xFeAs. The zero field experiments on underdoped (x=0.075) and optimally doped (x=0.1) samples rule out any static magnetic order above 1.6 K in these superconducting samples. From transverse field experiments in the vortex phase we deduce the temperature and field dependence of the superfluid density. Whereas the temperature dependence is consistent with a weak coupling BCS s-wave or a dirty d-wave gap function scenario, the field dependence strongly evidences unconventional superconductivity. We obtain the in-plane penetration depth of λ_{ab} (0) = 254(2)nm for LaO_{0.9}F_{0.1}FeAs and λ_{ab} (0) = 364(8)nm for LaO_{0.925}F_{0.075}FeAs. Further evidence for unconventional superconductivity is provided by the ratio of T_c versus the superfluid density, which is close to the Uemura line of hole doped high-T_c cuprates.

5 pages, 5 figures

References in corpus (15)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Very High Field Two-Band Superconductivity in LaFeAsO_0.89F_0.11
• Proximity of antiferromagnetism and superconductivity in LaO${}_{1-x}$F${}_x$FeAs: effective Hamiltonian from ab initio studies
• Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and Electron-type Superconductivity near Ferromagnetic Instability
• Electron Correlations in the Low Carrier Density LaFeAsO0.89F0.11 Superconductor (Tc = 28 K)
• Iron-based layered superconductor LaO${}_{1-x}$F${}_x$FeAs: an antiferromagnetic semimetal
• Upper critical field, Hall effect and magnetoresistance in the iron-based layered superconductor LaFeAsO_{0.9}F_{0.1-δ}
• Hall effect and magnetoresistance in the normal state of the superconductor LaO${}_{0.9}$F${}_{0.1-x}$FeAs
• Superconducting properties of Fe-based layered superconductor LaO${}_{0.9}$F${}_{0.1-\delta }$FeAs
• Even Parity, Orbital Singlet and Spin Triplet Pairing for Superconducting $La(O_{1-x}{F}_x)FeAs$
• Optical determination of the superconducting energy gap in electron-doped Pr_{1.85}Ce_{0.15}CuO_4
• Study of the in-plane magnetic penetration depth in the cuprate superconductor Ca_2-xNa_xCuO_2Cl_2: role of the apical sites

Cited by in corpus (71)

• Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
• The electronic phase diagram of the LaO1-xFxFeAs superconductor
• Iron-Based Superconductors: current status of materials and pairing mechanism
• Coexistence of static magnetism and superconductivity in SmFeAsO1-xFx as revealed by muon spin rotation
• Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor
• Evidence for nodal superconductivity in LaFePO
• Pairing State with a time-reversal symmetry breaking in FeAs based superconductors
• Fully Gapped Superconducting State Based on a High Normal State Quasiparticle Density of States in Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ Single Crystals
• Low temperature specific heat of the hole-doped Ba_{0.6}K_{0.4}Fe_2As_2 single crystals and electron-doped SmFeAsO_{0.9}F_{0.1} samples
• Unconventional London penetration depth in Ba(Fe0.93Co0.07)2As2 single crystals
• Superconductivity coexisting with phase-separated static magnetic order in (Ba,K)Fe${}_2$As${}_2$, (Sr,Na)Fe${}_2$As${}_2$ and CaFe${}_2$As${}_2$
• Interplay of Rare Earth and Iron magnetism in RFeAsO with R = La, Ce, Pr, and Sm: A muon spin relaxation study and symmetry analysis
• Coexistence of magnetic fluctuations and superconductivity in the pnictide high temperature superconductor SmFeAsO${}_{1-x}$F${}_x$ measured by muon spin rotation
• Evidence for Two Gaps and Breakdown of the Uemura Plot in Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ Single Crystals
• Muon-spin rotation studies of SmFeAsO_0.85 and NdFeAsO_0.85 superconductors
• Strong-coupling Spin-singlet Superconductivity with Multiple Full Gaps in Hole-doped Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ Probed by Fe-NMR
• Muon spin relaxation studies of magnetic order and superfluid density in antiferromagnetic NdOFeAs, BaFe2As2 and superconducting (Ba,K)Fe2As2
• 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
• Nodal Superconductivity with Multiple Gaps in SmFeAsO${}_{0.9}$F${}_{0.1}$
• Normal State Correlated Electronic Structure of Iron Pnictides
• Coexistence and competition of magnetism and superconductivity on the nanometer scale in underdoped BaFe1.89Co0.11As2
• MuSR studies of RE(O,F)FeAs (RE = La, Nd, Ce) and LaOFeP systems: possible incommensurate/stripe magnetism and superfluid density
• Lower Critical Fields of Superconducting PrFeAsO${}_{1-y}$ Single Crystals
• Evidence for electromagnetic granularity in the polycrystalline iron-based superconductor LaO0.89F0.11FeAs
• Coexistence of two order parameters and a pseudogaplike feature in the iron-based superconductor LaFeAsO_(1-x)F_x
• Large decrease in the critical temperature of superconducting LaFeAsO0.85 compounds doped with 3% atomic weight of nonmagnetic Zn impurities
• Caloric Determination of the Upper Critical Fields and Anisotropy of NdFeAsO1-xFx Single Crystals
• On the electronic structure of electron doped LaOFeAs as seen by X-ray absorption spectroscopy
• Anisotropy of superconducting single crystal SmFeAsO_(0.8)F_(0.2) studied by torque magnetometry
• Point-contact Andreev-reflection spectroscopy in ReFeAsO_{1-x}F_x (Re = La, Sm): Possible evidence for two nodeless gaps
• Evidence for two distinct anisotropies in the oxypnictide superconductors SmFeAsO_(0.8)F_(0.2) and NdFeAsO_(0.8)F_(0.2)
• Upper and lower critical fields in NdFeAs(O,F) single crystals : a study by Hall probe magnetization and specific heat
• Muon-spin-spectroscopy study of the penetration depth of FeTe0.5Se0.5
• Enhancement of Superfluid Stiffness, Suppression of Superconducting T_c and Field-induced Magnetism in the Pnictide Superconductor LiFeAs
• Pairing symmetry and properties of iron-based high temperature superconductors
• Insular superconductivity in Co-doped iron pnictide CaFe${}_{1-x}$Co${}_x$AsF
• Multiple Gaps and Superfluid Density from Interband Pairing in Iron Oxypnictides
• Full Gap Superconductivity in Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$ Probed by Muon Spin Rotation
• Lower critical field and SNS-Andreev spectroscopy of 122-arsenides: Evidence of nodeless superconducting gap
• Electronic properties of LaOFFeAs in the normal state probed by NMR/NQR
• SrPt${}_3$P: two-band single-gap superconductor
• Energy-scale phenomenology and pairing via resonant spin-charge motion in FeAs, CuO, heavy-fermion and other exotic superconductors
• The single- vs. two-gap scenario: the specific heat and the thermodynamic critical field of BeAu superconductor
• Vortex state in iron-based superconductors with collinear antiferromagnetic cores
• Signature of multigap nodeless superconductivity in fluorine-doped NdFeAsO
• Competition/Coexisitence of Magnetism and Superconductivity in Iron Pnictides Probed by Muon Spin Rotation
• Optical Study of LaO_0.9F_0.1FeAs: Evidence for a Weakly Coupled Superconducting State
• Large magnetic penetration depth and thermal fluctuations in a Ca${}_{10}$(Pt${}_3$As${}_8$)[(Fe${}_{1-x}$Pt${}_x$)${}_2$As${}_2$]${}_5$ (x=0.097) single crystal
• Time-reversal invariant and fully gapped unconventional superconducting state in the bulk of the topological Nb0.25Bi2Se3
• Superfluid density and superconducting gaps of RbFe_{2}As_{2} as a function of hydrostatic pressure
• Enhanced anisotropic spin fluctuations below tetragonal-to-orthorhombic transition in LaFeAs(O_{1-x}F_x) probed by ^{75}As and ^{139}La NMR
• Correlated electrons in Fe-As compounds: a quantum chemical perspective
• Superconducting gap structure in ambient-pressure-grown $\mathrm{La}{\mathrm{O}}_{0.5}{\mathrm{F}}_{0.5}\mathrm{Bi}{\mathrm{S}}_2$
• Determination of the pairing state in iron-based superconductors through neutron scattering
• Scanning tunneling microscopy of the 32 K superconductor (Sr1-xKx)Fe2As2
• Supercell studies of the Fermi surface changes in the electron-doped superconductor LaFeAsO${}_{1-x}$F${}_x$
• Conventional Superconductivity in Fe-Based Pnictides: the Relevance of Intra-Band Electron-Boson Scattering
• Superconducting gap symmetry of the noncentrosymmetric superconductor W3Al2C
• High superconducting anisotropy and weak vortex pinning in Co doped LaFeAsO
• Relationships between Superconductivity and Nematicity in FeSe${}_{1-x}$Te${}_x$ ($x=0-0.5$) Films Studied by Complex Conductivity Measurements
• Determination of characteristic muon precession and relaxation signals in FeAs and FeAs2, possible impurity phases in pnictide superconductors
• Nodeless superconductivity in quasi-one-dimensional Nb2PdS5: A muSR study
• Phase separation at the magnetic-superconducting transition in La${}_{0.7}$Y${}_{0.3}$FeAsO${}_{1-x}$F${}_x$
• Two-Gap Superconductivity in CaFe_{0.88}Co_{0.12}AsF Revealed by Temperature Dependence of the Lower Critical Field H_{c1}^c(T)
• Crossover between magnetism and superconductivity in low H-doped LaFeAsO
• Direct measurement of the temperature dependence of the magnetic penetration depth in Ba(Fe${}_{1-x}$Ni${}_x$)${}_2$As${}_2$ superconductors
• Unconventional superconductivity originating from disconnected Fermi surfaces in the iron-based compound
• Type-II superconductivity in the Dirac semimetal PdTe2
• Broken time-reversal symmetry in cubic skutterudite-like superconductor Y${}_3$Ru${}_4$Ge${}_{13}$
• Study of the Two-Gap Superconductivity in GdO(F)FeAs by ScS-Andreev Spectroscopy
• Pressure-Induced Enhancement of Superfluid Density in Transition Metal Dichalcogenides with and without Charge Density Wave