Related papers: Scanning tunneling microscopy of the 32 K supercon…

In this letter, we report that the superconductivity transition temperature in beta-Fe1.01Se increases from 8.5 to 36.7 K under applied pressure of 8.9 GPa. It then decreases at higher pressure. A dramatic change in volume is observed at…

Single crystals of mixed alkaline earth metal iron arsenide materials of Ba1-xSrxFe2As2 and Ba0.5Sr0.5(Fe1-yCoy)2As2 are synthesized via the self-flux method. Ba1-xSrxFe2As2 display spin-density wave features (TN) at temperatures…

We synthesized the samples $Ba_{1-x}M_xFe_2As_2$ (M=La and K) with $ThCr_2Si_2$-type structure. These samples were systematically characterized by resistivity, thermoelectic power (TEP) and Hall coefficient ($R_H$). $BaFe_2As_2$ shows an…

The superconducting film of (Li1-xFex)OHFeSe is reported for the first time. The thin film exhibits a small in-plane crystal mosaic of 0.22 deg, in terms of the FWHM (full-width-at-half-maximum) of x-ray rocking curve, and an excellent…

We present a detailed investigation of the magnetic and superconducting properties of Ca1-xNaxFe2As2 single crystals with x = 0.00, 0.35, 0.50, and 0.67 by means of the local probe techniques Moessbauer spectroscopy and muon spin relaxation…

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…

The Dirac semimetal PdTe${}_2$ becomes superconducting at a temperature $T_{c}=1.6$~K. Thermodynamic and muon spin rotation experiments support type-I superconductivity, which is unusual for a binary compound. A key property of a type-I…

The 57Fe M\"ossbauer spectroscopy was applied to an iron-based layered superconductor LaO0.89F0.11FeAs with a transition temperature of 26 K and its parent material LaOFeAs. Throughout the temperature range from 4.2 to 298 K, a singlet…

Inelastic light scattering studies on single crystal of electron-doped Ca(Fe0.95Co0.05)2As2 superconductor, covering the tetragonal to orthorhombic structural transition as well as magnetic transition at TSM ~ 140 K and superconducting…

Following the discovery of superconductivity in an iron-based arsenide LaO1-xFxFeAs with a superconducting transition temperature (Tc) of 26 K[1], Tc was pushed up surprisingly to above 40 K by either applying pressure[2] or replacing La…

We report the discovery of a low-temperature phase transition in Bi_2Sr_2Ca(Ni_xCu_{1-x})_20_8 high temperature superconductor. This transition manifests itself as a sharp reduction of the thermal conductivity of the samples at a…

Granular superconductivity occurs when microscopic superconducting grains are separated by non-superconducting regions through which they communicate by Josephson tunneling to establish the macroscopic superconducting state [1]. Although…

The recently discovered high-T$_c$ superconductor Ca$_{1-x}$La$_{x}$FeAs$_{2}$ is a unique compound not only because of its low symmetry crystal structure, but also because of its electronic structure which hosts Dirac-like metallic bands…

We extract the density of states (DOS) from the scanning tunneling spectroscopy data for Ba$_{1-x}$K$_x$Fe$_2$As$_2$ superconductor. The obtained sample DOS is composed of two ordinary $s$-wave types from the band at $\Gamma$ point and a…

CeRh2As2 is a newly discovered candidate of multiphase heavy-fermion superconductor (Tc=0.3 K) with intriguing physical properties. Here, we employ soft point-contact spectroscopy to investigate its energy gap behaviors in both the normal…

The discovery of high-temperature superconductivity in Fe-based compounds [1,2] has triggered numerous investigations on the interplay between superconductivity and magnetism [3] and, more recently, on the enhancement of transition…

A series of layered nickel-based LaO$_{1-x}$F$_x$NiAs compounds with x=0 to 0.15 are synthesized by solid state reactions. The pure LaONiAs exhibits bulk superconductivity with Tc $\sim$ 2.75 K. Partial substitution of oxygen by fluorine…

A deep understanding of the character of superconductivity in the recently discovered Fe-based oxypnictides ReFeAsO1-xFx (Re = rare-earth) necessarily requires the determination of the number of the gaps and their symmetry in k space, which…

Recent discovery of oxypnictide superconductor LaFeAs(O,F) (LFAO-F) with the critical temperature (Tc) of 26 K and succeeding revelation of much increased Tc upon substitution of La for other rare earth elements (such as Sm, leading to ~43…

A strong disorder characterized by a small product of the Fermi vector kF and the electron mean free l drives superconductors towards insulating state. Such disorder can be introduced by making the films very thin. Here, we present 3-nm…