Use of fluxoid quantization in the measurement of the inductance of single-junction SQUIDs

Calculations of the change in the flux linking a superconducting ring when a change in the fluxoid quantum state is induced are presented, taking into account the effect of thermodynamic fluctuation on the transition. A method is described by which this calculated flux value can be used to provide a calibration in a measurement of the inductance of the ring. The measurement procedure described is useful for rings with an inductance of 10−8 H and smaller, and will give results accurate to about 2%.