Related papers: Improved superconducting properties of MgB2
We report here synthesis, structural, DC magnetization, and transport studies of new BiS2 based layered LaO0.5F0.5BiS2 superconductor [1]. The sample was synthesized by conventional solid state route via vacuum encapsulation technique at…
The specific heat of high-purity $\rm Ba_{0.68}K_{0.32}Fe_2As_2$ single crystals with the highest reported superconducting $T_c$ = 38.5 K was studied. The electronic specific heat, $C_p$, below $T_c$ shows two gap features, with $\Delta_1…
The fluctuating diamagnetic magnetization Mfl at constant field H as a function of temperature and the isothermal magnetization Mfl vs H are measured in MgB2, above the superconducting transition temperature. The expressions for Mfl in…
We have synthesized MgB2/Pb planar junctions to study the temperature and field dependence of the superconducting energy gap of MgB2. The major peak occurs at Delta of about 2 meV, and this corresponds to a 2Delta/kBTc value of 1.18. While…
We measured the specific heat, the magnetization, and the magnetoresistance of a single crystal of ZrB12, which is superconducting below Tc ~ 6 K. The specific heat in zero field shows a BCS-type superconducting transition. The normal- to…
With the relatively high critical temperature (Tc) of 39 K1 and the high critical current density (Jc) of > 100000 A/cm2 in moderate fields, magnesium diboride (MgB2) superconductors could offer the promise of important large-scale and…
Recent discoveries of superconductivity in hydrogen-rich compounds stabilized by high pressures have shown that a critical temperature of superconductivity Tc can reach near room temperature values. The current studies focus on the search…
A simple two-band model with interband scattering of intraband pairs is applied to MgB$_2$ superconductivity. An adjustable parameters set is chosen. The calculated $T_c$ vs doping, isotope exponent and the heat capacity jump are in…
Superconducting at 40 K MgB2 -samples were obtained by direct reaction from elements in molybdenum crucibles under argon pressure. Pressure allows to provide annealing at temperature up to 1400oC, that resulting in rise of Tc and…
We present a study of electrical transport properties of $R$Bi$_2$ ($R$ = La, Ce) under hydrostatic pressure up to $\sim$ 2.5 GPa. These measurements are complemented by thermodynamic measurements of the specific heat on CeBi$_2$ at…
We report the high-pressure synthesis of novel superconductor MgB$_2$ and some related compounds. The superconducting transition temperature of our samples of MgB$_2$ is equal to 36.6 K. The MgB$_2$ lattice parameters determined via X-ray…
The Ru0.9Sr2YCu2.1O7.9 sample being synthesized by high-pressure high-temperature solid-state reaction underwent (weak) ferromagnetic transition at 150 K followed by superconducting transition at 30 K. It showed clear Meissner signal in the…
We report on the preparation of dense monofilamentary MgB2/Ni and MgB2/Fe tapes with high critical current densities. In annealed MgB2/Ni tapes, we obtained transport critical current densities as high as 2.3*105 A/cm2 at 4.2 K and 1.5 T,…
Bulk samples of MgB2 were prepared with 5, 10, and 15% wt.% Y2O3 nanoparticles added using a simple solid-state reaction route. Transmission electron microscopy (TEM) showed a fine nanostructure consisting of ~3-5 nm YB4 nanoparticles…
The Tb-123 phase has been synthesized in single-phase form with the composition TbSr2Cu2.7Mo0.3O7 by solid-state reaction route and its phase purity is confirmed by neutron powder diffraction experiments. As-synthesized sample does not show…
Two sets of MgB2 samples doped with up to 5 at. % of Al were prepared in different laboratories using different procedures. Decreases in the a and c lattice parameters were observed with Al doping confirming Al substitution onto the Mg…
Experimental studies of the electric and heat currents in the normal, superconducting and mixed states of high T$_c$ superconductors (HTcS) lead to characterization, complementary to data obtained from equilibrium property based techniques.…
We report measurements of the superconducting critical temperature Tc of polycrystalline MgB2 samples containing isotopically pure (10)B and (11)B under quasi-hydrostatic pressure conditions in He pressure media up to 44 GPa. Measurements…
We have successfully synthesized MgB2 thick films on 4H-SiC substrate by hybrid physical-chemical deposition (HPCVD). The films have transition temperature TC above 40 K. X-ray diffraction (XRD) shows the c-axis oriented structure of MgB2,…
We report on syntheses and electron transport properties of polycrystalline samples of diborides (AB2) with different transition metals atoms (A=Zr,Nb,Ta). The temperature dependence of resistivity, \rho(T), and ac susceptibility of these…