Related papers: Close correlation between superconducting transiti…
Exploration of new superconductors has always been one of the research directions in condensed matter physics. We report here a new layered heterostructure of [(Fe,Al)(OH)2][FeSe]1.2, which is synthesized by the hydrothermal ion-exchange…
The influence of a partial substitution with sulphur into Te sites on the crystal, electronic and magnetic structures of FeTe is investigated by DFT calculations. The results reveal a phase transition from the antiferromagnetic…
Superconductivity in the cuprate superconductors and the Fe-based superconductors is realized by doping the parent compound with charge carriers, or by application of high pressure, to suppress the antiferromagnetic state. Such a rich phase…
The influence of various strains on crystal and electronic structures of superconducting FeSe has been studied ab initio. We consider changes in the Fermi surface nesting with a vector Q=(0.5,0.5)*(2\pi /a) as crucial for rising…
The discoveries of iron-based superconductors with relatively high transition temperature are under intense experimental and theoretical investigation. Here we present magnetotransport measurements on FeSe superconductor under hydrostatic…
We studied the correlation among structure and transport properties and superconductivity in the different $A_x$Fe$_2$Se$_2$ single crystals ($A$ = K, Rb, and Cs). Two sets of (00$l$) reflections are observed in the X-ray single crystal…
By using high-quality single crystals, we quantitatively compare the transport properties between LiFeAs and LiFeP superconductors with compensated electron and hole carriers. The low-temperature resistivity follows the Fermi-liquid $AT^2$…
The recently discovered iron arsenide superconductors, which display superconducting transition temperatures as high as 55 K, appear to share a number of general features with high-Tc cuprates, including proximity to a magnetically ordered…
There are several FeSe based superconductors, including the bulk FeSe, monolayer FeSe thin film, intercalated KxFe2-ySe2 and Li1-xFexOHFeSe, etc. Their normal states all show metallic behavior. The key player here is the FeSe layer which…
Superconductivity in low carrier density metals challenges the conventional electron-phonon theory due to the absence of retardation required to overcome Coulomb repulsion. In quantum critical polar metals, the Coulomb repulsion is heavily…
The single-layer FeSe films grown on SrTiO3 (STO) substrates have attracted much attention because of its record high superconducting critical temperature (Tc). It is usually believed that the composition of the epitaxially grown…
We have measured the magnetotransport properties and Hall effect of a series of epitaxial NbN films grown on (100) oriented single crystalline MgO substrate under different conditions using reactive magnetron sputtering. Hall effect…
The relaxations of conductivity after a temporary change of carrier density n_s during the waiting time t_w have been studied in a strongly disordered two-dimensional electron system in Si. At low enough n_s < n_g (n_g - the glass…
The Fermi surfaces of Fe-pnictide superconductors are fairly two-dimensional (2D), and it has thus come as a surprise that recent penetration depth and thermal conductivity measurements on systems of the 122 type have reported c-axis…
The presumably unconventional superconductor Beta-FeSe was deposited by radio frequency sputtering and molecular beam epitaxy (MBE) from two elementary sources. Superconducting thin films were grown in (001)-orientation on MgO(100) and…
Density-functional calculations are presented for high-pressure structural phases of S and Se. The structural phase diagrams, phonon spectra, electron-phonon coupling, and superconducting properties of the isovalent elements are compared.…
We have investigated the suppression of the superconducting transition temperature, Tc, with an increase of the residual resistivity, \rho_0, through the substitution of M (M = Co, Ni, Zn) for Fe in Fe1-yMySe0.3Te0.7 single crystals, in…
We formulate a theory of doped magnetic semiconductors such as Ga$_{1-x}$Mn$_x$As which have attracted recent attention for their possible use in spintronic applications. We solve the theory in the dynamical mean field approximation to find…
We present ARPES data taken from the structurally simplest representative of iron-based superconductors, FeSe, in a wide temperature range. Apart from the variations related to the nematic transition, we detect very pronounced shifts of the…
The discovery of high-temperature (Tc) superconductivity in monolayer FeSe on SrTiO3 raised a fundamental question whether high Tc is commonly realized in monolayer iron-based superconductors. Tetragonal FeS is a key material to resolve…