Related papers: Site specific spin dynamics in BaFe2As2: tuning th…

Despite the wealth of experimental data on the Fe-pnictide compounds of the KFe2As2-type, K = Ba, Ca, or Sr, the main theoretical work based on multiorbital tight-binding models has been restricted so far to the study of the related 1111…

We investigate the nature of the SDW (Spin Density Wave) transition in the underdoped regime of an iron-based high Tc superconductor Ba(Fe1-xCox)2As2 by 75As NMR, with primary focus on a composition with x = 0.02 (T_SDW = 99 K).We…

The semiconductor-semiconductor transition of La2RuO5 is studied by means of augmented spherical wave (ASW) electronic structure calculations as based on density functional theory and the local density approximation. This transition has…

We have performed an angle-resolved photoemission spectroscopy study of the new superconductor Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ in the low energy range. We report the observation of an anomaly around 25 meV in the dispersion of…

Quantum transitions in Fe-based systems are believed to involve spin, charge and nematic fluctuations. Complex structural phase diagram in these materials often emphasizes importance of covalency in their exotic properties, which is…

The iron-based LaFeAsO$_{1-x}$F$_x$ recently discovered by Hosono's group is a fresh theoretical challenge as a new class of high-temperature superconductors. Here we describe the electronic structure of the material and the mechanism of…

A microscopic model for the FeAs plane in the newly discovered Iron-based superconductors is proposed with the emphasis on the role of the orbital degeneracy between the Fe $3d_{xz}$ and $3d_{yz}$ orbital in the crystal field environment.…

We revisit the electronic structure of BaFe$_2$As$_2$, the archetypal parent compound of the Fe-based superconductors, using angle-resolved photoemission spectroscopy (ARPES). Our high-resolution measurements of samples detwinned by the…

Two magnon excitations and the nodal spin density wave (SDW) gap were observed in BaFe2As2 by Raman scattering. Below the SDW transition temperature (TSDW) nodal SDW gap opens together with new excitations in reconstructed electronic…

A new hight Tc Fe-based compound system, AFe2As2 with A = K, Cs, K/Sr and Cs/Sr has been found. Through electron-doping, Tc of the A = K and Cs compounds rises to ~37 K, and finally enter a spin-density-wave state (SDW) through further…

Among numerous hypotheses, recently proposed to explain superconductivity in iron-based superconductors [1-9], many consider Fermi surface (FS) nesting [2, 4, 8, 10] and dimensionality [4, 9] as important contributors. Precise determination…

The iron-based superconductors had a significant impact on condensed matter physics. They have a common structural motif of a two-dimensional square iron lattice and exhibit fruitful physical properties as a strongly correlated electron…

We present details of carrier properties in high quality ${\rm Ba(Fe_{1-x}Co_{x})_2As_2}$ single crystals obtained from electronic Raman scattering. The experiments indicate a strong band and momentum anisotropy of the electron dynamics…

The superconducting fluctuations well inside the normal state of Fe-based superconductors were experimentally studied through the in-plane paraconductivity in several high-quality optimally-doped BaFe$_{2-x}$Ni$_x$As$_2$ crystals. These…

Using random-phase approximation spin-fluctuation theory, we study the influence of the hybridization between iron $d$-orbitals and pnictide $p$-orbitals on the superconducting pairing state in iron-based superconductors. The calculations…

In the metallic magnet Nb$_{1-y}$Fe$_{2+y}$, the low temperature threshold of ferromagnetism can be investigated by varying the Fe excess $y$ within a narrow homogeneity range. We use elastic neutron scattering to track the evolution of…

For a newly discovered iron-based high T_c superconducting parent material KFe2Se2, we present an effective three-dimensional five-orbital tight-binding model by fitting the band structures. The three t2g-symmetry orbitals of the five Fe 3d…

Temperature-dependent reflectivity measurements in the frequency range 85 - 7000 cm$^{-1}$ were performed on BaFe$_2$As$_2$ single crystals under pressure up to $\sim$5 GPa. The corresponding pressure- and temperature-dependent optical…

The recently discovered superconducting - spin density wave materials, containing Fe and As, have raised huge interest. However most materials prepared to date, suffer from a varying degree of content of foreign Fe-As phases, Fe2As, FeAs2…

Spin fluctuations in superconducting BaFe2(As1-xPx)2 (x=0.34, Tc = 29.5 K) are studied using inelastic neutron scattering. Well-defined commensurate magnetic signals are observed at ({\pi},0), which is consistent with the nesting vector of…