Related papers: Surface superconducting states in a polycrystallin…
We report variation of lattice structure in diborides (AB2) with different A atoms to identify the special case of MgB2 showing high Tc superconductivity. High purity MgB2 (Tc~39 K) has been prepared by direct reaction of the elements and…
We present a systematic investigation of superconductivity in a topological superconductor candidate $T_{\rm d}$-MoTe$_2$ in the few-layer limit. By examining multiple mechanically exfoliated samples with different thicknesses, substrates…
The two-dimensional Hubbard model exhibits superconductivity with d-wave symmetry even at half-filling in the presence of next-nearest neighbor hopping. Using plaquette cluster dynamical mean-field theory with a continuous-time quantum…
In this paper, we apply the two-band extension [1] of BCS theory [2] into the Mattis-Bardeen theory [3] to obtain the surface impedance of a two-band superconductor, and apply it to magnesium diboride (MgB2) for radiofrequency (RF)…
In this paper, we reported the structural properties and superconductivity of Mg(B1-xCx)2 compounds. Powder x-ray diffraction results indicate that the samples crystallize in a hexagonal AlB2-type structure. Due to the chemical activity of…
High-pressure resistivity experiments were performed on the recently discovered superconductor, MgB2. Tc decreases quasi-linearly with applied pressure to 1.4 GPa at a rate of -2.0(1) K/GPa, which is somewhat larger than that derived from…
The hydrostatic pressure effect on the newly discovered superconductor MgB2 has been determined. The transition temperature Tc was found to decrease linearly at a large rate of -1.6 K/GPa, in good quantitative agreement with the ensuing…
We report the experimental study of linear and nonlinear ac properties of two types of samples of MgB2 prepared by different technologies. A commercial sample (Alfa Aesar) demonstrates two stages of a broad phase transition, whereas…
In this paper we present scanning tunneling microscopy of Bi$_2$Se$_3$ with superconducting Nb deposited on the surface. We find that the topologically protected surface states of the Bi$_2$Se$_3$ leak into the superconducting over-layer,…
We report the synthesis and physical properties of a full Heusler compound, MgPd$_2$Sb, which we found to show superconductivity below $T_c$ = 2.2 K. MgPd$_2$Sb was obtained by a two-step solid-state reaction method and its purity and cubic…
We report the results of the measurement the ac conductivity of a Nb superconducting thin film in a swept dc magnetic field. In the mixed state the swept dc field creates vortices at the film surface which pass through the film and form the…
Using Scanning Tunneling Microscope at low temperature we explore the superconducting phase diagram in the $\pi$-band of the two-band superconductor MgB$_2$. In this band the peculiar shape of the local tunneling spectra and their dynamics…
Superconducting MgB(2) films with Tc = 38.6 K were prepared using a precursor-deposition, ex-situ post-processing approach. Precursor films of boron, ~0.5 micrometer thick, were deposited onto Al(2)O(3) (102) substrates by e-beam…
Two dimensional (2D) superconductivity was studied by magnetotransport measurements on single-atomic-layer Pb films on a cleaved GaAs(110) surface. The superconducting transition temperature shows only a weak dependence on the parallel…
We report the study of the polycrystalline MgB2 phase formation during the fabrication processes. Three major phases are identified in different sintering temperature ranges according to the corresponding superconducting properties and the…
LiBC, a semiconducting ternary borocarbide constituted of the lightest elements only, has been synthesized and characterized by x-ray powder diffraction, dielectric spectroscopy, and conductivity measurements. Utilizing an infrared…
The dc magnetoconductivity of the multisubband two-dimensional electron system formed on the liquid helium surface in the presence of resonant microwave irradiation is described, and a new mechanism of the negative linear response…
Samples of aligned MgB2 crystallites have been prepared, allowing for the first time the direct identification of an upper critical field anisotropy Hc2^{ab}/Hc2^{c}= xi_{ab}/xi_{c} ~ 1.73; with xi_{o,ab} ~ 70 A, xi_{o,c} ~ 40 A, and a mass…
We report first-principles calculations of the k- and T-dependent superconducting gap Delta(k,T) in MgB2 and its manifestation in various measured quantities. Because the Fermi surface has disconnected sheets with different electron-phonon…
The MgB2 superconductor synthesized in a flowing argon atmosphere using nanometer magnesium powder as the raw materials, denoted as Nano-MgB2, has been studied by the technique of in-situ high temperature resistance measurement (HT-RT…