Related papers: Large critical current density improvement in Bi-2…
We have previously shown for powders that Mo substitution into the CuO chains of YBa2Cu3O7 can create effective pinning centres which significantly increase the critical current density (j_c) in 7 T field by a factor of 4 and 10 at 50 and…
One important factor affecting the critical current density in type-II superconductors is the formation of artificial pinning centers. Hence, the engineering of pinning centers in superconducting systems has garnered considerable attention.…
We have conducted pulsed transport measurements on c-axis oriented magnesium diboride films over the entire relevant ranges of magnetic field $0 \alt H \alt H_{c2}$ (where \hcu is the upper critical field) and current density $0 \alt j \alt…
Monofilamentary MgB2-wires with a 2- or 3-component sheath containing mechanical reinforcing stainless steel (SS) were prepared and characterized. In direct contact to the superconductor Nb, Ta or Fe was used. For a selection of samples…
Cold high pressure densification (CHPD) is presented as a new way to substantially enhance the critical current density of in situ MgB2 wires at 4.2 and 20 K at fields between 5 and 14 T. The results on two binary MgB2 wires and an alloyed…
We have studied the local critical current density, jc, in the superconductor thin film of bilayer structures consisting of YBa2Cu3O7 and the ferromagnets La2/3Ca1/3MnO3 and SrRuO3, respectively, by means of quantitative magneto-optics. A…
In this letter, we report the first successful fabrication of dense, metal-clad MgB2 superconductor wires as well as the first demonstration of high transport Jc of greater than 36,000 A/cm2 in MgB2. The fabrication technique that we…
A series of polycrystalline SmFeAs1-xOx bulks was prepared to systematically investigate the influence of sample density on flux pinning properties. Different sample densities were achieved by controlling the pelletizing pressure. The…
In magnetic superconductors vortices polarize spins nonuniformly and repolarize them when moving. At a low spin relaxation rate and at low bias currents vortices carrying magnetic polarization clouds become polaron-like and their velocities…
(Ba,K)Fe2As2 superconducting wires and tapes are fabricated by using hot isostatic pressing (HIP) technique, and their superconducting properties are studied. In the HIP round wire, transport critical current density (Jc) at 4.2 K has…
We report non-Cu critical current densities of 4.09 * 10^9 A/m^2 at 12 T and 2.27 * 10^9 A/m^2 at 15 T obtained from transport measurements on a Ti-alloyed RRP Nb3Sn wire after irradiation to a fast neutron fluence of 8.9 * 10^21 m^-2.…
We report herein a high and isotropic critical-current density Jc for BaFe2(As,P)2 epitaxial films. The isotropy of Jc with respect to the magnetic-field direction was improved significantly by decreasing the film growth rate to 2.2…
The effect of high magnetic fields on the current carrying properties of both MgB2 bulks and Fe-sheathed tapes was investigated following different thermal sequences. It is found that application of a large magnetic field during processing…
The high resistivity of many bulk and film samples of MgB2 is most readily explained by the suggestion that only a fraction of the cross-sectional area of the samples is effectively carrying current. Hence the supercurrent (Jc) in such…
Doping is one of the most relevant paths to tune the functionality of cuprates, it determines carrier density and the overall physical properties of these impressive superconducting materials. We present an oxygen doping study of…
Few-unit cell thick Bi$_2$Sr$_2$CaCu$_2$O$_{8+x}$ (Bi-2212) layers have recently attracted much interest due to their extreme anisotropy and two-dimensional superconductivity, although they are typically susceptible to ambient conditions.…
The high upper critical field and low anisotropy of iron-based superconductors make them being particularly attractive for high-field applications. However, the current carrying capability needs to be enhanced by overcoming the weak-link…
Ex-situ Powder-In-Tube MgB2 tapes prepared with ball-milled, undoped powders showed a strong enhancement of the irreversibility field H*, the upper critical field Hc2 and the critical current density Jc(H) together with the suppression of…
Conductor insulation is one of the key components needed to make Ag-alloy clad Bi2Sr2CaCu2O8+x (Bi-2212/Ag) superconducting round wire (RW) successful for high field magnet applications as dielectric standoff and high winding current…
Improving transport current has been the primary issue for practical application of superconducting wires and tapes. However, the porous nature of powder-in-tube (PIT) processed iron-based superconducting tapes is thought to be one of the…