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Energy. The Equinox Summit held in Waterloo Canada 2011 (2011 Equinox Summit: Energy 2030 http://wgsi.org/publications-resources) identified electricity use as humanity's largest contributor to greenhouse gas emissions. Our appetite for electricity is growing faster than for any other form of energy. The communiqué from the summit said 'Transforming the ways we generate, distribute and store electricity is among the most pressing challenges facing society today.... If we want to stabilize CO2 levels in our atmosphere at 550 parts per million, all of that growth needs to be met by non-carbon forms of energy' (2011 Equinox Summit: Energy 2030 http://wgsi.org/publications-resources). Superconducting technologies can provide the energy efficiencies to achieve, in the European Union alone, 33–65% of the required reduction in greenhouse gas emissions according to the Kyoto Protocol (Hartikainen et al 2003 Supercond. Sci. Technol.16 963). New technologies would include superconducting energy storage systems to effectively store power generation from renewable sources as well as high-temperature superconducting systems used in generators, transformers and synchronous motors in power stations and heavy-industry facilities. However, to be effective, these systems must be superior to conventional systems and, in reality, market penetration will occur as existing electrical machinery is written off. At current write-off rates, to achieve a 50% transfer to superconducting systems will take 20 years (Hartikainen et al 2003 Supercond. Sci. Technol.16 963).

Bi-2212 stands out as the only HTS (high temperaure superconductor) that can be fabricated as a round wire. This makes Bi-2212 a perfect candidate for winding cables and coils without significantly changing present magnet technology.

An international team led by University of Toronto physicists has developed a simple new technique to induce high-temperature superconductivity in a semiconductor for the first time - using Scotch Tape.

An international team of researchers at the University of Vienna unveiled the superconducting pairing mechanism in Calcium doped graphene using the ARPES method. Their results are published in the reputed journal Nature Communications.

Applications for superconducting wires, which carry electricity without resistance when cooled to a critical temperature, include underground transmission cables, transformers and large-scale motors and generators. But these applications require wires to operate under different temperature and magnetic field regimes.  

The comprehensive ρ(T) measurements and the consequent resistivity curvature mapping (RCM) on Y0.7Ca0.3Ba2Cu3O7−δ thin films (doping levels p = 0.08–0.21) elucidate a phase diagram for the whole doping range. This phase diagram further strengthens a view that the 'normal' phase in hole-doped cuprates should be divided into a strong superconducting (SC) fluctuation phase and the 'real' normal phase in which there is no significant influence of SC. The temperature of superconducting fluctuations Tf as a function of p was calculated using the Ginzburg–Landau model for layered superconductors. Comparisons between Tf and the Nernst temperature establish the origin of the Nernst effect as SC fluctuations. Some of the details in ρ(T) cannot be fully understood by the existing models and call for a more sophisticated theory of carrier dynamics in cuprates.

Researchers from the RIKEN Center for Life Science Technologies and Chiba University have developed a high-temperature superconducting wire with an ultra-thin polyimide coating only 4μm thick, more than 10 times thinner than the conventional insulation used for high-temperature superconducting wires.

To improve energy efficiency, companies are increasingly researching into new methods of reducing losses during energy transmission and generation. High-temperature superconductors (HTS) have been ranked amongst the most effective technologies being developed. Besides this, the growing trend towards new power generation sources and smart grids are the main market drivers for superconducting components such as cables, generators, and storage systems.

Researchers in Germany have claimed a breakthrough: a material that can act as a superconductor — transmit electricity with zero resistance — at room temperature and above. Superconductors offer huge potential energy savings, but until now have worked only at temperatures of lower than about -110 °C.

We studied a thin superconducting NbN film in magnetic fields up to 8 T above the zero-temperature limit by means of time-domain terahertz and scanning tunneling spectroscopies in order to understand the vortex response. Scanning tunneling spectroscopy was used to determine the optical gap and the upper critical field of the sample. The values obtained were subsequently used to fit the terahertz complex conductivity spectra in the magnetic field in the Faraday geometry above the zero-temperature limit. These spectra are best described in terms of the Coffey–Clem self-consistent solution of a modified London equation in the flux creep regime.

“We want to see this process used,” Larbalestier said. “We want to build lots of magnets out of Bi-2212, get the wire cost down, useable lengths way up and make Bi-2212 the precursor of new generations of round, twisted, multifilament, high-temperature superconductor wires that will be revolutionize superconducting applications.”

Furthermore, a curious result of the present investigation is that there is no change in the superconducting transition temperature (Tc) up to a doping level of 10 wt%.

These results verify that the developed DC superconducting cable is reliable and fulfils all the requirements necessary for successful use in various power applications including railway systems.