Related papers: Enhancement of Critical Current Density in low lev…

MgB2/Fe tapes with 2.5-15 at.% ZrB2 additions were prepared through the in situ powder-in-tube method. Compared to the pure tape, a significant improvement in the in-field critical current density Jc was observed, most notably for 10 at.%…

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…

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 effect of nanoscale-SiC doping of MgB2 was investigated using transport and magnetic measurements. It was found that there is a clear correlation between the critical temperature Tc, the resistivity r, the residual resistivity ratio,…

Phase-pure polycrystalline Ba0.6K0.4+xFe2As2 with were prepared using a one-step solid-state reaction method. We found that over-doping of potassium can improve critical current density (Jc). High-field Jc for samples with x = 0.1 is three…

In order to establish the doping dependence of the critical current properties in the iron-based superconductors, the in-plane critical current density (Jc) of BaFe2As2-based superconductors, Ba1-xKxFe2As2 (K-Ba122), Ba(Fe1-xCox)2As2…

Measurements of the critical current density (Jc) by magnetization and the upper critical field (Hc2) by magnetoresistance have been performed for hafnium-doped MgB2. There has been a remarkable enhancement of Jc as compared to that by ion…

We evaluated the doping effects of carbohydrate (malic acid, C4H6O5), from 0wt% to 30wt% of total MgB2, on the phase, lattice parameters, critical temperature, resistivity, and upper critical field of MgB2 superconductor. The lattice…

Powdered and sintered MgB2 samples have been characterized through magnetic measurements performed from T = 5 K up to few degrees above the transition temperature of about 39 K. We found that the sintered samples behave as well-connected…

The nano-SiC doped MgB2/Fe wires were fabricated using a powder-in-tube method and an in-situ reaction process. The depression of Tc with increasing SiC doping level remained rather small due to the counterbalanced effect of Si and C…

Fe-sheathed MgB2 tapes with cheap stearic acid, Mg stearate and Zn stearate doping were prepared through the in situ powder-in-tube method. It is found that Jc, Hirr, and Hc2 were significantly enhanced by doping. Compared to the pure…

The effect of doping MgB2 with carbon nanotubes on transition temperature, lattice parameters, critical current density and flux pinning was studied for MgB2-xCx with x = 0, 0.05, 0.1, 0.2 and 0.3. The carbon substitution for B was found to…

We report the synthesis and characterization of graphite (C) doped MgB2-xCx (x = 0.0, 0.1, 0.2 and 0.3) samples. The crystal structure and microstructural characterization have been investigated by x-ray diffractometer and transmission…

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…

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…

An improvement of the transport critical current density, Jc, of MgB2 wires was obtained after addition of 10 wt.% B4C powders, after reaction at 800 C: Jc values of 1.10^4 A/cm2 at 4.2 K and 9T were obtained for wires of 1.11 mm diameter…

The temperature dependence of the upper critical field, Hc2, for both field directions in partially substituted polycrystalline MgB2 was determined. Whereas the suppression of Tc is similar for aluminum and carbon substituted samples, Hc2…

The doping dependence of the critical current density, $J_{c}$, was measured in a series of high quality c-axis oriented ${\rm Bi_2Sr_2CaCu_2O_{8+\delta}}$ thin films. For each doping level we measured the temperature dependence of $J_{c}$.…

A comprehensive study of the effects of carbohydrate doping on the superconductivity of MgB2 has been conducted. In accordance with the dual reaction model, more carbon substitution is achieved at lower sintering temperature. As the…