Related papers: Anisotropic scattering rate in Fe substituted Bi22…
Recently, high resolution angle-resolved photoemission spectroscopy has been used to determine the detailed momentum dependence of the superconducting gap in the high temperature superconductor Bi-2212. In this paper, we first describe…
We have performed systematic resistivity and inelastic neutron scattering measurements on Fe$_{0.98-z}$Ni$_z$Te$_{0.5}$Se$_{0.5}$ samples to study the impact of Ni substitution on the transport properties and the low-energy ($\le$ 12 meV)…
We have performed high-resolution angle-resolved photoemission spectroscopy on Fe-based superconductor LiFeAs (Tc = 18 K). We reveal multiple nodeless superconducting (SC) gaps with 2D/kBTc ratios varying from 2.8 to 6.4, depending on the…
We have investigated the superconducting(SC)-gap anisotropy for several Ba-doped KFe$_2$As$_2$ samples using laser-based angle-resolved photoemission spectroscopy. We show that the SC-gap anisotropy and node positions drastically change…
The gap anisotropy in Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ is revisited in the framework of a d-wave scenario in view of the recent angle-resolved photoemission experiment. Based on a tight-binding fit to the normal state dispersion, a detail…
The Fe K X-ray absorption near edge structure (XANES) of BaFe2-xCoxAs2 superconductors was investigated. No appreciable alteration in shape or energy position of this edge was observed with Co substitution. This result provides experimental…
Non-magnetic impurities in iron-based superconductors can provide an important tool to understand the pair symmetry and they can influence significantly the transport and the superconducting behaviour. Here, we present a study of the role…
We used high-energy resolution angle-resolved photoemission spectroscopy to extract the momentum dependence of the superconducting gap of Ru-substituted Ba(Fe$_{0.75}$Ru$_{0.25}$)$_2$As$_2$ ($T_c = 15$ K). Despite a strong out-of-plane…
We use laser-based Angle-Resolved Photoemission Spectroscopy (ARPES) to study how chemical substitution modifies the electronic properties of the Bi2(Se{1-x}Tex)3 (BiSeTe) family of topological insulators. We find that increasing the Te…
We studied nearly optimally Ni-substituted BaFe$_{2-x}$Ni$_x$As$_2$ (BFNA) single crystals with $T_C \approx 18.5$\,K. In irreversible magnetization measurements, we determined the field dependence of the critical-current density and…
We study the superconducting(SC)-gap anisotropy of the \Gamma-centered hole Fermi surface in optimally doped FeTe_{0.6}Se_{0.4} (T_c = 14.5 K), using laser-excited angle-resolved photoemission spectroscopy (ARPES). We observe sharp…
In Fe-based superconductors, electron doping is often realized by the substitution of transition-metal atoms for Fe. In order to investigate how the electronic structure of the parent compound is influenced by Zn substitution, which…
Angle-resolved photoemission spectroscopy (ARPES) is used to study the scattering rates of charge carriers from the hole pockets near Gamma in the iron-based high-Tc hole doped superconductors KxBa1-xFe2As2 x=0.4 and KxEu1-xFe2As2 x=0.55$…
In a recent paper Kendziora et al concluded that the superconducting gap in overdoped Bi-2212 is isotropic. From data obtained from electronic Raman scattering measurements, their conclusion was based on the observation that pair breaking…
We have investigated the effect of atomic substitutions in the FeSe system, which exhibits the simplest crystal structure among the iron-based superconductors. An enhancement of the superconducting transition temperature Tc was observed…
We report superconducting (SC) properties of stoichiometric LiFeAs (Tc = 17 K) studied by small-angle neutron scattering (SANS) and angle-resolved photoemission (ARPES). Although the vortex lattice exhibits no long-range order, well-defined…
Angle-resolved photoemission spectroscopy (ARPES) is used to study the band dispersion and the quasiparticle scattering rates in two ferropnictides systems. Our ARPES results show linear-in-energy dependent scattering rates which are…
We report measurements of the momentum dependence of the superconducting gap in Bi_2Sr_2CaCu_2O_{8+x} (Bi2212) with angle-resolved photoemission spectroscopy using a dense sampling of the Brillouin zone in the vicinity of the Fermi surface.…
The Cu substitution effect on the superconductivity of LiFeAs has been studied in comparison with Co/Ni substitution. It is found that the shrinking rate of the lattice parameter c for Cu substitution is much smaller than that of Co/Ni…
We present a systematic analysis of the energy gap in underdoped Bi2212 superconductor as a function of temperature and hole doping level. Within the framework of the theoretical model containing the electron-phonon and…