most abundant elements, and there are enormous deposits of bastnaesite and monazite from which neodymium is easily extracted. Despite the low cost of the elements themselves, at the present time the process for making these materials in the proper form is very costly. It often takes time to develop methods to reduce the price, and as long as a process is costly, the material will not be used in large quantities. In addition, the manufacturer of a particular material sells his product to people who make components, which are introduced into products that are then sold to consumers or industry. Consequently, there is a small profit incentive for the developer of the technology, because he is under the price pressure of a long train of customers.

Superconductors illustrate many of the problems inherent in bringing a new material from discovery to widespread application in a short time. Although superconductors were discovered before the First World War, they were not understood. Nevertheless, it was recognized that a material that could carry electricity without loss of energy should be extremely marketable. When it was discovered that these properties held true only for very low current levels and at very low temperatures, enthusiasm died out.

Solving the problem of the temperature and current constraints on superconductivity became a matter for pure science research. Some progress was achieved through empirical theories such as London’s and later through the work of Bardeen, Cooper, and Schrieffer. New materials, such as niobium nitrate, that had slightly higher transition temperatures were discovered. Then Matthias applied his genius to devising more or less empirical rules, which led to the discovery of materials with higher transition temperatures, culminating at 23.2 K. Although this was an important discovery, it was not sufficient to maintain market pull.

Other people were working in completely different materials and found that some oxides, for example, have transition temperatures above 10 K. During that time there was also work in France on the lanthanum copper oxide-based material and yttrium copper oxide. These materials produced higher conductivity but were not tried at low temperatures.

Müller and Bednorz, working at the IBM Laboratory in Zurich, proposed that these oxides might work at a higher temperature. In early 1986, Müller and Bednorz published results showing the initial appearance of superconductivity at 40 K, a sudden jump by a factor of 2. Within three months, it was announced in the People’s Republic of China that beginning superconductivity at 73 K and zero resistance at 80 K had been observed. The result was soon reproduced in the United States, Europe, and Japan. There are indications that a sample was superconducting at a temperature of 244 K, very close to room temperature. Thus, from the time of the first theoretical treatment of superconductivity in the 1930s, it has taken more than 40 years for superconductors to be brought to the stage where it is realistic to talk about widespread application of this technology.

Let us consider likely potential uses and effects of these new supercon-



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