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SQUIDs and their applications

Gordon B. Donaldson 

University of Strathclyde, Department of Physics and Applied Physics, John Anderson Building, 107 Rottenrow, Glasgow G4 0NG, United Kingdom


SQUIDs (Superconducting Quantum Interference Devices) are the most sensitive electromagnetic detectors available, and have been used in many modes as detectors of weak magnetic sources. This talk will discuss the science underlying the operation of SQUIDs and as an introduction to the more specialist talks that follow, will introduce some of their 'routine' applications, such as their use in adult and fetal cardiography and in precision metrology. Finally, noting that the ultimate sensitivity of these devices is 'quantum limited', and set only by the Heisenberg Uncertainty Principle, it will come as no surprise that they have been employed in some very exotic experimental situations. The latest of these involves their deployment in the recently launched Gravity Probe B satellite which is to verify a previously untested prediction of the General Theory of Relativity; In this project, which is to last 1 year, SQUIDs will detect the gyroscopic precession of spinning balls with an angular precision corresponding to that subtended by a human hair at a distance of 20km.


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Presentation: invited oral at NATO Advanced Research Workshop, by Gordon B. Donaldson
See On-line Journal of NATO Advanced Research Workshop

Submitted: 2004-08-05 11:44
Revised:   2009-06-08 12:55