Within a few years of Josephson's seminal paper on superconducting tunneling, devices were being fabricated to measure a wide variety of electromagnetic quantities. Before the end of the decade' SQUID devices were being offered for sale. In the 1970's, SQUIDs began transitioning from laboratory instruments to applications in medicine, geology and materials science. Over the last 40 years of commercial sales, SQUID systems have generated well over a half billion dollars in product revenues. This paper discusses the evolution of the many small businesses that began to offer SQUIDs as commercial products, their product areas and their successes and failures.
Perspectives on the 50th Anniversary of SQUIDs (Superconducting Quantum Interference Devices) by Bob Fagaly.