Related papers: Why Does Undoped FeSe Become A High Tc Superconduc…
We investigated the superconducting transition and the pinning properties of undoped and Ag-doped FeSe0.94 at magnetic fields up to 14 T. It was established that due to Ag addition the hexagonal phase formation in melted FeSe0.94 samples is…
We report measurements of resistance and ac magnetic susceptibility on FeSe single crystals under high pressure up to 27.2 kbar. The structural phase transition is quickly suppressed with pressure, and the associated anomaly is not seen…
We have carried out a pressure study of the unconventional superconductor FeTe0.6Se0.4 up to 1.5 GPa by neutron scattering, resistivity and magnetic susceptibility measurements. We have extracted the neutron spin resonance energy and the…
Resolving the interplay between magnetic interactions and structural properties in strongly correlated materials through a quantitatively accurate approach has been a major challenge in condensed matter physics. Here we apply highly…
We report resistivity measurement under pressure in single crystals of SrFe_2As_2, which is one of the parent materials of Fe-based superconductors. The structural and antiferromagnetic (AFM) transition of T_0 = 198 K at ambient pressure is…
Since the discovery of superconductivity\cite{1} at 26 K in oxy-pnictide $LaFeAsO_{1-x}F_x$, enormous interests have been stimulated in the fields of condensed matter physics and material sciences. Among the five different structures in…
Over the past few years Fe chalcogenides (FeSe/Te) have advanced to the forefront of Fe-based superconductors (FeBS) research. The most intriguing results thus far are for intercalated and monolayer FeSe, however experimental studies are…
The isostructural transition in the tetragonal phase, with sizable change in the anion-height, is realized in heavily H-doped LaFeAsO and (La,P) co-doped CaFe$_2$As$_2$. In these compounds, the superconductivity with higher-Tc (40~50 K) is…
The spin-fluctuation effect in the Se-substituted system Fe$_{1+\delta}$Te$_{1-x}$Se$_x$ ($x$ = 0, 0.05, 0.12, 0.20, 0.28, 0.33, 0.45, 0.48 and 1.00; $0<\delta < 0.12$) has been studied by the measurements of the X-ray diffraction, the…
FeTe is a prototypical parent compound of iron-based superconductors. While bulk FeTe is non-superconducting with a long-range bicollinear antiferromagnetic order, superconductivity has been achieved in thin films. However, the approaches…
The quantum spin fluctuations of the S = 1/2 Cu ions are important in determining the physical properties of the high-transition temperature (high-Tc) copper oxide superconductors, but their possible role in the electron pairing for…
Nematicity and magnetism are two key features in Fe-based superconductors, and their interplay is one of the most important unsolved problems. In FeSe, the magnetic order is absent below the structural transition temperature $T_{str}=90$K,…
High pressure provides a powerful means for exploring unconventional superconductivity which appears mostly on the border of magnetism. Here we report the discovery of pressure-induced heavy fermion superconductivity up to 2.5 K in the…
We report the analysis of fluctuation conductivity (FLC) and pseudogap (D*) in Fe-based superconductor SmFeAsO0.85 with Tc = 55 K derived from resistivity experiments. In the FLC analysis distinct 2D-3D (MT-AL) crossover typical for…
The magnetic properties of Fe1.03Te under hydrostatic pressure up to p ~ 5.7 GPa were investigated by means of muon spin rotation, dc magnetization, and neutron depolarization measurements. With increasing pressure the antiferromagnetic…
We use inelastic neutron scattering to study the effect of a magnetic field on the neutron spin resonance (Er = 3.6 meV) of superconducting FeSe (Tc = 9 K). While a field aligned along the in-plane direction broadens and suppresses the…
Reentrant superconductivity has been observed in the candidate spin-triplet superconductor UTe$_2$ as a function of the magnetic field applied along the hard axis. Resistivity measurements have shown, a broadened superconducting transition…
In order to investigate the effects of in-plane strain on the superconductivity of FeSe, epitaxial thin films of FeSe were fabricated on CaF$_2$ substrates. The films are compressed along the a-axis and their superconducting transition…
Synthesis, electrical and magnetic characterization of superconducting FeSe0.85 compound is reported. An anomaly in the magnetization against temperature around 90K is observed. Magnetic characterization of a commercial compound with…
The electronic energy structures and magnetic properties of layered superconductors $R$Ni$_2$B$_2$C, $R$Fe$_4$Al$_8$ and FeSe are systematically studied, by using the density functional theory (DFT). The calculations allowed us to reveal a…