Related papers: LiFeAs: An Intrinsic FeAs-based Superconductor wit…

A series of layered CeO$_{1-x}$F$_x$FeAs compounds with x=0 to 0.20 are synthesized by solid state reaction method. Similar to the LaOFeAs, the pure CeOFeAs shows a strong resistivity anomaly near 145 K, which was ascribed to the…

We report the first nitrogen-containing iron-pnictide superconductor ThFeAsN, which is synthesized by a solid-state reaction in an evacuated container. The compound crystallizes in a ZrCuSiAs-type structure with the space group P4/nmm and…

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…

The response of the worldwide scientific community to the discovery in 2008 of superconductivity at Tc = 26 K in the Fe-based compound LaFeAsO_{1-x}F_x has been very enthusiastic. In short order, other Fe-based superconductors with the same…

We have synthesized two iron fluo-arsenides $A$Ca$_2$Fe$_4$As$_4$F$_2$ with $A$ = Rb and Cs, analogous to the newly discovered superconductor KCa$_2$Fe$_4$As$_4$F$_2$. The quinary inorganic compounds crystallize in a body-centered…

We report pressure-induced superconductivity in a single crystal of CaFe2As2. At atmospheric pressure, this material is antiferromagnetic below 170 K but under an applied pressure of 0.69 GPa becomes superconducting, with a transition…

Superconductivity with transition temperature Tc above 40 K was observed in protonated FeSe (Hy-FeSe) previously with the ionic liquid of EMIM-BF4 used in the electrochemical process. However, the real superconducting phase is not clear…

The recently discovered quaternary arsenide oxide superconductor La[O1-xFx]FeAs with the superconducting critical transition temperature (Tc) of 26 K [1], has been quickly expanded to another high-Tc superconducting system beyond copper…

We utilize ultrafast optical measurement to study the quasiparticle relaxation in stoichiometric LiFeAs and nearly optimally doped (BaK)Fe2As2 crystals. According to our temperature-dependent studies of LiFeAs, we have observed…

A LiFeAs single crystal with $T_c^{onset}$$\sim$19.7 K was grown successfully in a sealed tungsten crucible using the Bridgeman method. The electrical resistivity experiments revealed a ratio of room temperature to residual resistivity…

The stoichiometric "111" iron-based superconductor, LiFeAs, has attacted great research interest in recent years. For the first time, we have successfully grown LiFeAs thin film by molecular beam epitaxy (MBE) on SrTiO3(001) substrate, and…

The FeSe superconductor and its related systems have attracted much attention in the iron-based superconductors owing to their simple crystal structure and peculiar electronic and physical properties. The bulk FeSe superconductor has a…

Potassium intercalated FeSe has been reported as a superconductor with superconducting transition temperatures ($T_{\rm c}$'s) of 30-48 K. However, there is no clear answer to identify the relationship between the surface morphology,…

Following a recent proposal by Burrard-Lucas et al. [unpublished, arXiv: 1203.5046] we intercalated FeSe by Li in liquid ammonia. We report on the synthesis of new LixFe2Se2(NH3)y phases as well as on their magnetic and superconducting…

Single crystalline FeTe$_{0.61}$Se$_{0.39}$ with a sharp superconducting transition at $T_{\textrm{c}} \sim$ 14 K is synthesized via slow furnace cooling followed by low-temperature annealing. The effect of annealing on the chemical and…

The recently discovered high temperature superconductor F-doped LaFeAsO and related compounds represent a new class of superconductors with the highest transition temperature (Tc) apart from the cuprates. The studies ongoing worldwide are…

We have performed temperature dependent tunneling spectroscopy on an impurity-free surface area of a LiFeAs single crystal. Our data reveal a highly unusual temperature evolution of superconductivity: at $T_c^*=18$~K a partial…

We have performed several high-pressure resistivity experiments on the recently discovered superconductors La[O_{0.89}F_{0.11}]FeAs and Ce[O_{0.88}F_{0.12}]FeAs. At ambient pressure, these materials have superconducting onset temperatures…

We report a high-pressure study on the heavily electron doped Lix(NH3)yFe2Se2 single crystal by using the cubic anvil cell apparatus. The superconducting transition temperature Tc = 44 K at ambient pressure is first suppressed to below 20 K…

Located at crystal voids, interstitial anion electrons (IAEs) have diverse topologies, which may be tuned to achieve new properties. Elucidating the role of IAEs in electron-phonon coupling (EPC), and using it to design new electride…