Related papers: The Microstrain-Doping Phase Diagram of the Iron P…
With the proposed Hund's rule correlation picture, i.e. the fluctuating Fe local moments with the As-bridged antiferromagnetic superexchange interactions, the exceptional collapsed tetragonal phase and related phase transitions observed in…
We report the observation of a nonlinear elastoresistivity response for the prototypical underdoped iron pnictide Ba(Fe$_{0.975}$Co$_{0.025}$)$_2$As$_2$. Our measurements reveal a large quadratic term in the isotropic ($A_{1g}$) electronic…
We report the effect of applied pressures on magnetic and superconducting order in single crystals of the aliovalent La-doped iron pnictide material Ca$_{1-x}$La$_{x}$Fe$_{2}$As$_{2}$. Using electrical transport, elastic neutron scattering…
We report experimental evidence for the phase diagram of doped cuprate superconductors as a function of the micro-strain (e) of the Cu-O bond length, measured by Cu K-edge EXAFS, and hole doping (d). This phase diagram shows a QCP at…
Critical current density was studied in single crystals of Ba(Fe$_{1-x}$Co$_x$)$_2$As$_2$ for the values of $x$ spanning the entire doping phase diagram. A noticeable enhancement was found for slightly underdoped crystals with the peak at…
Inspired by naturally occurring sulfide minerals, we present a new family of iron-based superconductors. A metastable form of FeS known as the mineral mackinawite forms two-dimensional sheets that can be readily intercalated by various…
Domain phases in ultrathin Fe/Ni/W(110) films with perpendicular anisotropy have been studied using the ac magnetic susceptibility. Dynamics on time scales of minutes to hours were probed by quenching the system from high temperature to the…
High temperature superconductivity emerges in the vicinity of competing strongly correlated phases. In the iron-based superconductor $Ba(Fe_{1-x}Co_{x})_{2}As_{2}$, the superconducting state shares the composition-temperature phase diagram…
We carried out combined transport and optical measurements for BaFe2As2 and five isostructural transition-metal (TM) pnictides. The low-energy optical conductivity spectra of these compounds are, to a good approximation, decomposed into a…
Ultra-thin FeAs is of interest both as the active component in the newly identified pnictide superconductors, and in spintronic applications at the interface between ferromagnetic Fe and semiconducting GaAs. Here we use first-principles…
We have discovered a new homologous series of iron pnictide oxides (Fe2As2)(Can+2(Al,Ti)nOy)[n = 2,3,4]. These compounds have perovskite-like blocking layers between Fe2As2 layers. The structure of new compounds are tetragonal with space…
We report the first comprehensive study of the high temperature form ($\alpha$-phase) of iron disilicide. Measurements of the magnetic susceptibility, magnetization, heat capacity and resistivity were performed on well characterized single…
The biaxially textured growth of superconducting Co-doped BaFe2As2 (Ba-122) thin films has been realized on ion beam assisted deposition (IBAD) MgO coated conductor templates by employing an iron buffer architecture. The iron pnictide…
Superconductivity was recently observed in the iron-arsenic-based compounds with a superconducting transition temperature (Tc) as high as 56K [1-7], naturally raising comparisons with the high Tc copper oxides. The copper oxides have…
Iron-based superconductors Ba0.7Rb0.3Fe2As2 and CaFe1.92Co0.08As2 of the '122' family have been investigated by means of the 14.41-keV Moessbauer transition in 57Fe versus temperature ranging from the room temperature till 4.2 K. A…
Phase diagrams play a primary role in the understanding of materials properties. For iron-based superconductors (Fe-SC), the correct definition of their phase diagrams is crucial because of the close interplay between their…
We have successfully synthesized a new superconducting phase of FeTe1-xSx with a PbO-type structure. It has the simplest crystal structure in iron-based superconductors. Superconducting transition temperature is about 10 K at x = 0.2. The…
The phase diagram of LaFeAs$_{1-x}$P$_x$O system has been extensively studied through hole- and electron-doping as well as As/P-substitution. It has been revealed that there are three different superconducting phases with different Fermi…
Microscopic, structural, transport and thermodynamic measurements of single crystalline Ba(Fe1-xTMx)2As2 (TM = Ni and Cu) series, as well as two mixed TM = Cu / Co series, are reported. All the transport and thermodynamic measurements…
We have constructed a pressure$-$temperature ($P-T$) phase diagram of $P$-induced superconductivity in EuFe$_2$As$_2$ single crystals, via resistivity ($\rho$) measurements up to 3.2 GPa. As hydrostatic pressure is applied, an…