The history of SQUID activity in Japan and the United States is fascinating and is perhaps instructive as an indication of what might occur in other areas of SCE. As outlined above, the United States has had and continues to have leading-edge sensor technologies, both LTS and HTS. It had small companies selling products for over 20 years with no competition anywhere in the world. One of them, Quantum Design, continues to be profitable by supplying research instruments. But in general, the United States appears to have lost its momentum in this field. In particular, it seems to have lost its desire to innovate at the system level. Through its focus on existing products, BTi neglected to develop the technology of whole-head systems until after CTF (Canada) and Neuromag (Finland) and SSL in Japan had done so. Conductus has not capitalized on its early entry into the HTSQUID applications market and has not developed HTS systems. Much of the technology developed at IBM, UC Berkeley, and the University of Maryland has not yet been utilized commercially.1
In contrast, Japan entered SQUID R&D very late, over 20 years after the formation of the first small U.S. company, SHE. In six years or so, largely due to the activities of SSL, not only did Japan create sensor technology comparable to that of the United States,2 but at the system level Japan moved ahead. There is no 256-channel LTS MEG system in the United States, no SQUID systems integrated with refrigerators, no HTS NDE prototype being used routinely, and no 64-channel HTS MCG system. All these are now developed in Japan, at least to a demonstration system level. It is true that in neither country are there large obvious markets for these systems, but there are many possible and speculative markets. In order to investigate such applications and markets, first a prototype system is needed. Thus, it seems likely that the Japanese SQUID groups and companies are more likely to first find and develop these markets, as they have systems. There is also interesting SQUID system progress in Europe, for example at Juelich and at a number of universities.
The WTEC panelists are led to wonder whether there is a parallel between the SQUID area and other SCE applications such as wireless. The United States had the four small companies entering the market first, while Japan is funding R&D at AMTEL, the Western Alliance, and at ISTEC. Who can say which will be the successful approach in 20 years? Will some of the concerns of the late 1980s come to pass, that the U.S. interest will burn itself out, while Japan persists for success in the long term? Certainly the SQUID precedent is a lesson that having technology and the early entry of small companies into the market does not guarantee eventual success. There is, however, one important difference between SQUIDs and wireless applications. The latter are seen by DOD agencies as important dual-use technologies, whereas the former, except for some interest from the Navy in the project at IBM and the Air Force in NDE of aging aircraft, are of little interest to DOD, implying more consistent funding for wireless than for SQUID R&D. Overall, although SQUID technology at the component sensor level is more advanced in the United States than in Japan, activity to develop new systems and applications, either LTS or HTS, appears limited at present. Consequently, if large SQUID markets develop, Japan (and also Europe) are likely to be strong competitors. This is in contrast to a decade ago, when the United States had a dominant position.
2The noise level of HTS sensors is probably lower in the United States than in Japan.