The most widely used superconducting materials are based on Nb-Ti alloys with Ti contents ranging from 46-50 weight % Ti. These alloys of Nb and Ti have both high strength and ductility and can be processed to achieve high critical current densities that make them ideal candidates for magnet and applications. Nb-Ti based superconductors are commercially produced in long uniform lengths and cost...

this paper represents the performance of a squirrel-cage high temperature superconducting induction/ synchronous motor (hts-ism) based on nonlinear electrical equivalent circuit. the structure of the hts-ism is the same as that of the squirrel-cage type induction machine, and the secondary windings are fabricated by the use of the hts wires. it has already been shown that based on the experimen...

We describe the decomposition of Abrikosov vortices into decoupled pancake vortices in superconductors having both electron and hole charge carriers. We estimate the critical current of such a decomposition, at which a superconducting-normal state transition occurs, and find that it is very sensitive to the magnetic field and temperature. The effect can be observed in recently synthesized self-...

Inhomogeneity of the properties of YBcr2Cu307 epitaxial c-oriented films has been investigated. Using a low temperature SEM the lateral distribution of local critical temperature has been determined with spatial resolution of 2 pm. The technique provides a direct observation of the percolative character of the superconducting transition on a microbridge scale. It is shown for the first time tha...

The verification of topological superconductivity has become a major experimental challenge. Apart from the very few spin-triplet superconductors with p-wave pairing symmetry, another candidate system is a conventional, two-dimensional (2D) s-wave superconductor in a magnetic field with a sufficiently strong Rashba spin-orbit coupling. Typically, the required magnetic field to convert the super...

Stacks of superconducting tape can be used as composite bulk superconductors for both trapped field magnets and for magnetic levitation. Little previous work has been done on quantifying the levitation force behavior between stacks of tape and permanent magnets. This paper reports the axial levitation force properties of superconducting tape wound into pancake coils to act as a composite bulk c...

The critical field of a thin superconducting film with a blind circular hole is found theoretically. It is shown that the value of the critical field is sensitive to the bottom thickness, but the orbital momentum, i.e., the number of vortices which nucleate inside the hole, is not sensitive. A simple boundary condition for a steplike thin film is derived and used for comparative numerical analy...

The superconducting transition is studied within the one-loop RG in fixed dimension D = 3 and at the critical point. A tricritical behavior is found and, for κ > κc, an attractive charged fixed point, distinct from that of a neutral superfluid. The critical exponents of the continuous transition are evaluated and it is shown that the anomalous dimension of the gauge-field equals unity. This imp...

In magnetically coupled, planar ferromagnet-superconductor (F/S) hybrid structures, magnetic domain walls can be used to spatially confine the superconductivity. In contrast to a superconductor in a uniform applied magnetic field, the nucleation of the superconducting order parameter in F/S structures is governed by the inhomogeneous magnetic field distribution. The interplay between the superc...