Until the late 1980s, the generally accepted theory of electric superconductivity of metals was based on an understanding of the interaction between conduction electrons and electrons in crystals. The critical temperature of superconductivity was thought to be below about 23 degrees Kelvin (roughly -418 degrees Fahrenheit), but in the late 1980s, it was discovered that superconductors could have critical temperatures above 100 degrees K, which threw the theoretical understanding of the subject into confusion and controversy. The discovery also spurred an effort to find new materials with an even higher Tc, or temperature of superconductivity; perhaps as high as room temperature.
The process of developing a superconducting product that Linus Pauling and his associates thought might be viable took several months and much collaboration, beginning in early 1988. Along with Pauling, other members of the Linus Pauling Institute of Science and Medicine, including Zelek Herman, Emile Zuckerkandl, Ewan Cameron and Stephen Lawson, worked on the project. When the researchers finished the task, Pauling was ecstatic and invited Herman and Lawson to his home, giving them large mineral crystals as gifts and offering to inscribe their copies of General Chemistry to commemorate the occasion.
Their invention aimed to form a composite structure in which superconducting materials assumed the form of fine strands embedded in a wave-guiding matrix. The matrix restricted the superconducting current to a linear motion; however, the strands did not need to be straight, but could also be bent or interconnected into a network. This matrix would be built of a non-conducting material such as glass.
Once the superconducting material was mounted with the help of the matrix material, the entire set-up was stretched to minimize the diameter of the superconductive strands, in the process maximizing the critical temperature. Optimum strand diameters were thought to lie in the range of 50-2000 angstroms – a unit of measure that is one-ten billionth of a meter and is denoted by the symbol Å. For its part, the matrix material needed to be easily drawn into fine strands and not be superconducting. Pauling believed that
by selecting the best superconducting and matrix materials and the optimum strand diameter, it should be possible to obtain a composite superconductor with critical temperature above room temperature, critical magnetic field above 100 tesla, and critical current density above 108 amperes per square centimeter.
In the group’s patent description, a few variations on this technique were listed that were thought to increase its effectiveness. One variation involved the embedding of two types of superconducting materials into the matrix instead of one. A suitable composite structure of this type could include strands of lanthanum and tin embedded in glass with a softening temperature of about 950˚C.
The description also noted a couple of different ways that the matrix material and superconducting material could be joined together. In one variation, the matrix was constructed as a tube and the superconducting material poured in and afterwards “drawn,” or stretched. Then several of these tubes containing superconducting material were joined together and stretched simultaneously, over and over, the same way Italian millefiori glass beads are made. Another variation utilized the filling of a porous matrix with a liquefied superconductor, whereupon the whole apparatus was heated and stretched.
The group admitted to problems with these methods, but Pauling thought up solutions. One obstacle was that the melting point of glass might be lower than that of the superconducting material, which would make it impractical to draw glass or other material with the superconductor. Pauling’s method of solving this problem was to add a powder made up of the superconducting material to the glass in order to reinforce it.
Despite all the work that Pauling and other scientists were accomplishing, a New York Times article published October 16, 1988, declared that the U.S. was falling behind Japan in the race to commercialize superconductors. The author predicted that “major uses of the new materials are considered to be at least ten years away” but that “scientists envision superconductors that could eventually be used to make computers that operate at blazing speeds, highly efficient electric generators and transmission lines, and high-speed trains that would be suspended above their tracks by superconducting magnets.”
The article continued that the new superconductors could conduct electricity at temperatures as high as -235 degrees Fahrenheit, whereas previously it had been thought that superconductivity could occur only at about -420 degrees Fahrenheit. The new temperature, the article concluded, would be much easier to achieve in laboratories.
Richard Hicks, Vice President of LPISM at the time, wanted to license Pauling’s invention, “Technique for Increasing the Critical Temperature of Superconducting Materials,” to U.S. companies, but was met with little positive feedback. As such, he instead attempted to license the invention to Japanese companies after hearing that Japan was also interested in the commercialization of superconductors. No Japanese companies showed interest either, but the CIA did come calling to ask why the Institute wanted to license a patent to Japan. Over the course of their interview, the CIA representative showed extensive knowledge and interest in the project. In explaining the Institute’s position, Steve Lawson clarified that no American companies had been interested in the purchase, so LPISM was compelled to look to other countries.
In 1988, the same year that the LPISM research group had begun work on the high-temperature superconductor, Pauling, Hicks and Zuckerkandl set up the Superbio Corporation to administer the business side of the invention. Initially Pauling assumed the role of Chairman of Superbio and Richard Hicks was President. Pauling believed it would be successful and invested in the company, owning 300,000 shares in Superbio, Inc. by the end of August. On August 12, 1988, Superbio entered into discussions with the Du Pont Company, which wanted to evaluate Superbio’s information on superconductivity with a view to “possible business activity.” In turn, Du Pont Co. was sworn to secrecy regarding Superbio’s research.
Not long after, on August 31, 1988, Pauling and IBM drew up a draft agreement in which IBM agreed to purchase the patents and/or patent applications for high temperature superconductivity from Pauling for the sum of $10,000. The document described Pauling’s invention in detail, stating that it “provides a technique for increasing the critical temperature, critical magnetic field, and maximum current density” of superconducting materials. In addition, IBM was to pay Pauling “a royalty of five percent of the manufacturing cost of the patented portion of any apparatus made.” The patent would become fully paid when IBM had compensated Pauling to the tune of $2 million.
In early 1989, Superconductor News affirmed the fears voiced by the New York Times in October 1988 that the U.S. was falling behind Japan in the race to commercialize superconductors. Their January/February issue included a report on presentations given by the United States Superconductor Applications Association (the SCAA), which included Japanese developments in “SC power transmission, SC magnetic energy storage, SC generators, SC electromagnetic ships, SC electronics and computers, and the SC linear motor car (maglev).” Superconductor News also discussed the possibility of impending confirmation of superconductive materials that could operate at room temperature (Ambient Temperature Superconductors, or ASCs). Potential uses for room temperature avionics applications were listed as thermoelectricity, solid state synchron sources for x-ray lithography, and applications for earth and planetary sciences, medicine, biology, and physical sciences with Extra Low Frequency (ELF) magnetometry.
In response, the Exploratory Research and Development Center in Los Alamos, New Mexico, was set up to boost the U.S.’s superconductivity research infrastructure. The Center was interested in collaborating with Pauling after he sent them a letter in July 1989 in which he mentioned his patent application on high-temperature superconductivity, which by that point had been turned over to Superbio. Pauling’s faith in the company was evident – by the end of November 1990, he owned 900,000 shares of common stock with Superbio. Bolstered by the seeming momentum of Superbio, the interest of other companies in Pauling’s superconductivity invention, and a patent in the works, the future for this work looked promising.