Overview of Superconductivity and Challenges in Applications

Abstract

Considerable progress has been achieved during the last few decades in the various fields of applied superconductivity, while the related low temperature technology has reached a high level. Magnetic resonance imaging (MRI) and nuclear magnetic resonance (NMR) are so far the most successful applications, with tens of thousands of units worldwide, but high potential can also be recognized in the energy sector, with high energy cables, transformers, motors, generators for wind turbines, fault current limiters and devices for magnetic energy storage. A large number of magnet and cable prototypes have been constructed, showing in all cases high reliability. Large projects involving the construction of magnets, solenoids as well as dipoles and quadrupoles are described in the present book. A very large project, the LHC, is currently in operation, demonstrating that superconductivity is a reliable technology, even in a device of unprecedented high complexity. A project of similar complexity is ITER, a fusion device that is presently under construction. This article starts with a brief historical introduction to superconductivity as a phenomenon, and some fundamental properties necessary for the understanding of the technical behavior of superconductors are described.The introduction of superconductivity in the industrial cycle faces many challenges, first for the properties of the baseelements, e.g. the wires, tapes and thin films, then for the various applied devices, where a number of new difficulties had to be resolved. A variety of industrial applications in energy, medicine and communications are briefly presented, showing how superconductivity is now entering the market.

Superconductivity assisted change of the perpendicular magnetic anisotropy in V/MgO/Fe junctions

“…The influence of superconductivity on the OOP transition has been studied by performing micromagnetic simulations with MuMax3 for 10 nm thick, 0.4 × 0.4 µm 2 Fe(001) films under the influence of a superconducting vanadium layer. We simulated OOP hysteresis cycles where a correction to the applied field was added based on a typical Meissner effect (ME) hysteresis cycle (obtained from 36 , shown in Figure 6b inset), scaled for different values of field contribution from Meissner effect and adapted to the first and second critical fields of vanadium (correspondingly H c1 and H c2 ). The contribution from superconducting vortices was taken into account by using an in-group developed program that numerically solves the time dependent Ginzburg-Landau equations in order to simulate the behaviour of type II superconductors under magnetic fields 37 .…”

Military Applications of Superconductivity and Future Perspectives

“…HTS materials were discovered in 1987 and the market penetration has started only now i.e. 25 years later [26]. Similarly, we have yet to see any practical applications of oxypnictides since their discovery in 2008 due to their complex nature.…”

Ab initio investigation of electronic structure and optical properties of IrSn4

“…Various studies have been carried out with the aim of figuring out the mechanism of superconductivity in unconventional, as well as conventional, superconductors, and finally procuring room temperature superconductors. 1,2 Commonly, superconductivity may appear in a material if there are suitable circumstances, for example pressure, magnetic field, temperature, or chemical doping. So, this became to us the important query: what underlying physics lie behind the superconductivity which exists in one morph but not in others?…”