Recent observation of unusual vortex patterns in MgB(2) single crystals raised speculations about possible "type-1.5" superconductivity in two-band materials, mixing the properties of both type-I and type-II superconductors. However, the strict application of the standard two-band Ginzburg-Landau (GL) theory results in simply proportional order parameters of the two bands-and does not support t...

The application of flat superconductor rings has been investigated in the structure of inductive shieldtype high temperature superconducting fault current limiters, HTc-SFCL. A laboratory scale inductive shield-type HTc-SFCL has been designed and fabricated using flat superconductor rings. The fabrication process has been fully presented. YBCO powder has been used for the fabrication of superco...

Surface atomic-layer (SAL) superconductors consisting of epitaxially grown metal adatoms on a clean semiconductor surface have been recently established. Compared to conventional metal thin films, they have two important features: (i) space-inversion symmetry-breaking throughout the system and (ii) high sensitivity to surface adsorption of foreign species. These potentially lead to manifestatio...

This paper presents the analysis, design, construction and ac test results of low voltage single-phase resistive superconductor electrical current limiters. Two different types of resistive superconductor current limiter are presented: the first one is built with three concentric, cylindrical and helicoidal coils connected in parallel and the second one is built with two superposed cylindrical ...

A point-contact probe capable of operating down to temperatures of 1.5 K and in magnetic fields of up to 32 T was designed and constructed. With this probe, preliminary data was obtained on Pr2-xCexCuO4 (PCCO) which reproduced previously published data in fields up to 8 T and temperatures down to 4.2 K. What is a superconductor? A material that can carry current without resistance at temperatur...

Superconductor fault current limiter (SFCL) is an effective device to suppress high fault currents. This paper presents a comparative study of resistive and inductive fault current limiters from transient stability point of view.  Appropriate location and type of the limiters in a HV substation is selected by a qualitative approach based on the equal area criterion. Study system is simulated by...

By comparing the voltage-current (V − I) curves obtained before and after cutting a sample of 2HNbSe2, we separate the bulk and edge contributions to the transport current at various dissipation levels and derive their respective V − I curves and critical currents. We find that the edge contribution is thermally activated across a current dependent surface barrier. By contrast the bulk V − I cu...

Various macroscopic phenomena seen in high temperature superconductors (HTSC) under nonzero magnetic fields have inspired much interest in studying the phase diagram of vortex states of three dimensional (3D) layered type II superconductors. Experimentally, thermodynamic and transport phenomena have been intensively examined mainly in YBCO [1-3] and BSCCO [4]. The resistive broadening [5] in th...

We carry out extensive Monte Carlo simulations of the three-dimensional uniformly frustrated XY model with uncorrelated randomly perturbed couplings, as a model for the equilibrium behavior of an extreme type-II superconductor with quenched uncorrelated random point vortex pinning, in the presence of a uniform applied magnetic field. We map out the resulting phase diagram as a function of tempe...