do some more reading sji l think you will find they have come a long way, just google superconductors and rare earths.
How rare earth metals are used in superconductors
by Elizabeth M Young Created on: March 05, 2010
A superconductor is defined as "An element, inter-metallic alloy, or compound that will conduct electricity without resistance below a certain temperature." 1
The idea is that resistance causes energy that is flowing through the material to be lost.
The theory is that electrical current will flow forever in a closed loop of superconducting material in what is called a "macroscopic quantum phenomenon", or perhaps the closest thing that we will ever have to natural perpetual motion.
Type I, or "soft" superconductors are metals that have a bit of conductivity at room temperature, but actually require extreme cooling in order to provide the conditions for electrons to flow without resistance.
Type II, or "hard" superconductors work through a variety of stages and with complications that are not all understood! There is a transition temperature, or tc, where the free flow of electrons occurs, and the higher the tc, the better the superconductor. As a result, "hard" superconductors are supposed to require far less extreme measures in cooling the materials.
Lately, scientists are finding that using the properties of certain rare earth metals to "dope" or to affect the complex arrangements of magnetic fields, ions, electrons and so on in metal alloys, will not raise the temperature required for free and unrestricted flow of electricity in superconducting, but create additional conditions that are conducive to permanent electrical current in a closed system.
Various rare earth metals are tested in these complex constructions of metal alloys including: yttrium, erbium, neodymium, samarium, Europium, and Dysprosium.
All but Yttrium are lanthanoids on the periodic table of elements. Yttrium is the most desirable of the rare earths in some testing. Yttrium Barium Copper Oxide has been historically good for higher temperature conductivity. Neodymium has the highest magnetic properties. Erbium has magnetic and superconductivity properties. Lutetium is extremely difficult to extract and is rare.
In summary, the goal in superconductor development is to get to the higher temperatures (Tc) required to produce maximum conductivity, eliminating or reducing the need for supercooling. The rare earth metals are showing promise, in alloy with other metals and elements, in getting closer to that goal, but not always in ways that are understood, and with more of "less supercooling" than of "no supercooling at all" as the results.
Thursday, September 29, 2011 Innovative Superconductor Fibres Carry 40 Times More Electricity Wiring systems using highly-efficient superconductors have long been a dream of science, but researchers have faced such practical challenges such as finding pliable and cost-effective materials. Researchers at Tel Aviv University (TAU) have found a way to make the next generation of superconductors.
Dr. Boaz Almog and a team TAU's School of Physics and Astronomy have developed superconducting wires using fibres made of single crystals of sapphire to be used in high powered cables. Factoring in temperature requirements, each tiny wire can carry approximately 40 times more electricity than a copper wire of the same size.
First … sapphire? Isn’t that a gemstone?. Well yes, it is usually visualized as a deep blue gemstone variety. of the mineral corundum, an aluminium oxide (a-Al2O3), when it is a color other than red or dark pink (in which case the gem would instead be called a ruby, considered to be a different gemstone). Trace amounts of other elements such as iron, titanium, or chromium can give corundum blue, yellow, pink, purple, orange, or greenish color.
Now back to the sapphire superconductors… High power superconductor cables take up much less space and conduct energy more efficiently, making them ideal for deployment across grids of electricity throughout a city. They will also offer a more effective method for collecting energy from renewable sources, such as solar and wind energy. Superconducting wires can also be used for energy storage and enable devices, which enhance grid stability.
It is understood that these new superconductors were introduced at the Israel Vacuum Society Conference in June 2011, and will be shown at both the European Conference on Applied Superconductivity and the Association of Science Technology Centers Conference this fall.
Traditional copper wires are relatively inefficient because of overheating due to electrical resistance found in the metal, some of the energy that flows through the cables is cast off and wasted, causing the wires to heat up. But with superconductors, there is no resistance. A self-contained cooling system, which requires a constant flow of liquid nitrogen, keeps the wire in its superconducting state. Readily available, non-toxic, and inexpensive liquid nitrogen provides the perfect coolant.
To create their superconductors, the researchers turned to sapphire fibers, developed at the US-based Oakridge National Lab and lent to the TAU team. Coated with a ceramic mixture using a special technique, these single-crystal fibers, slightly thicker than a human hair, have made innovative superconductors. Even with the benefit of liquid nitrogen, researchers were still hard pressed to find a material that would make the ideal superconductor. Superconductors coated on crystal wafers are effective but too brittle, and although superconductors on metallic tapes had some success, the product is too expensive to manufacture in mass quantities.
Superconductors could help in bring the power generated at renewable energy sources closer to the demand. Wind turbines or solar panels are usually located in remote places such (e.g. offshore lines, rural areas) and there is clearly a need to enable the efficient deliver the current to urban demand areas. These superconductors can traverse the long distances without losing any of the energy to heat due to electrical resistance.
Superconducting cables could also be an efficient way to move large amounts of power through big cities. As Dr, Almog noted "If you want to supply current for a section of a city like New York, you will need electric cables with a total cross-section of more than one meter by one meter. Superconductors have larger current capacities using a fraction of the space.”
TAU's mission is actually broader that solely developing a superior superconductor. It is understood and appreciated that TAU is also dedicated to making this technology accessible and exciting as a way to capture the imagination of aspiring scientists. (Now there is forward thinking!)
If you would like to read the original story, as presented by the Friends of Tel Aviv University, just click on