The Laser Switch in SQUID Measurements: Fundamental Experiments and Low Frequency Noise Reduction
We are developing a laser-driven superconducting switch. The switch has been used in several fundamental physics experiments which utilize SQUIDs, and in a noise reduction scheme for low-frequency SQUID measurements. The experiments include characterization studies of the laser switch itself, a direct measurement of the pinning force on a single vortex, the measurement of the Cooper pair mass, a study of the Aharonov-Bohm effect, and a measurement of the kinetic inductance of a superconducting thin-film. The noise reduction scheme is based on modulating the input circuit of a SQUID at a frequency above its 1/f knee. The demodulated output is then devoid of the SQUID noise below the modulation frequency. This paper reviews these experiments and reports on their status.
KeywordsKinetic Inductance Input Circuit Conditional Probability Function Input Coil Laser Switch
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