Related papers: Carbon-substituted MgB2 single crystals

We report anisotropic dc magnetic susceptibility $\chi(T)$, electrical resistivity $\rho(T)$, and heat capacity $C(T)$ measurements on the single crystals of CaFe$_{2-x}$Co$_x$As$_2$ for $x$ = 0 and 0.06. Large sized single crystals were…

We present data on temperature-dependent anisotropy of the upper critical field of MgB$_2$ obtained from the analysis of measurements on high purity, low resistivity polycrystals. The anisotropy decreases in a monotonic fashion with…

The reflectivity $R (\omega)$ of $ab$-oriented Mg$_{1-x}$Al$_x$(B$_{1-y }$C$_y$)$_2$ single crystals has been measured by means of infrared microspectroscopy for $1300<\omega<17000$ cm$^{-1}$. An increase with doping of the scattering rates…

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…

Two single crystalline samples with the same nominal composition of Rb0.8Fe2Se2 prepared via slightly different precursor routes under the same thermal processing conditions were investigated at ambient and high pressures. One sample was…

We report a $^{11}$B NMR line shape and spin-lattice relaxation rate ($1/(T_1T)$) study of pure and lightly carbon doped MgB$_{2-x}$C$_{x}$ for $x=0$, 0.02, and 0.04, in the vortex state and in magnetic field of 23.5 kOe. We show that while…

Single crystals of Ce-doped (La,Pr)OBiS2 superconductors, multinary rare-earth elements substituted ROBiS2, were successfully grown. The grown crystals typically had a size of 1-2 mm and a plate-like shape with a well-developed c-plane. The…

This paper presents a brief review on the reported anisotropic properties of MgB2, in the superconducting state (e.g. upper critical field Hc2, field penetration depth, coherence length, energy gap) as well as in the normal state (e.g.,…

Single crystals of Ba(Fe$_{1-x}$Ru$_x$)$_2$As$_2$, $x<0.37$, have been grown and characterized by structural, magnetic and transport measurements. These measurements show that the structural/magnetic phase transition found in pure…

Doping of MgB2 by nano-SiC and its potential for improvement of flux pinning was studied for MgB2-x(SiC)x/2 with x = 0, 0.2 and 0.3 and a 10wt% nano-SiC doped MgB2 samples. Co-substitution of B by Si and C counterbalanced the effects of…

A comparative study of pure, SiC, and C doped MgB2 wires has revealed that the SiC doping allowed C substitution and MgB2 formation to take place simultaneously at low temperatures. C substitution enhances Hc2, while the defects, small…

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…

Magnetization, susceptibility, specific heat, resistivity, neutron and x-ray diffraction have been used to characterize the properties of single crystalline CaFe2-xNixAs2 as a function of Ni doping for x varying from 0 to 0.1. The combined…

The discovery of superconductor in magnesium diboride MgB2 with high Tc (39 K) has raised some challenging issues; whether this new superconductor resembles a high temperature cuprate superconductor(HTS) or a low temperature metallic…

We report resistivity and magnetization of single crystal MgB2, focusing on the broadening of superconducting (SC) transition in magnetic fields. In-plane and out-of-plane resistivity indicate that the broadening of superconducting…

We have studied the evolution of superconducting and normal state properties of neutron irradiated Mg(B$_{.962}$C$_{.038}$)$_2$ wire segments as a function of post exposure annealing time and temperature. The initial fluence fully…

The recently discovered superconductivity in MgB2 has captured world attention due to its simple crystal structure and relatively high superconducting transition temperature Tc=39K. It appears to be generally accepted that it is…

Heavy carbon doping of MgB$_2$ is studied by first principles electronic structure studies of two types, an ordered supercell (Mg(B$_{1-x}$C$_{x}$)$_{2}$,x=0.0833) and also the coherent potential approximation method that incorporates…

We report phase formation, and detailed study of magnetization and resistivity under magnetic field of MgB2 polycrystalline bulk samples prepared by Fe-tube encapsulated and vacuum (10-5 torr) annealed (750 0C) route. Zero-field-cooled…

A series of doping experiments are reported for MgB2 conductors that have been synthesized using doped boron fibers prepared by chemical vapor deposition(CVD) methods. Undoped MgB2 samples prepared from CVD prepared fibers consistently give…