Title :
A precise null-balancing technique (PNB) for the 10 V Josephson junction array voltage standard system
Author :
Yoshida, Haruo ; Kozakai, Tuneoki ; Murayama, Yasushi
Author_Institution :
Adv. Labs. Ltd., Miyagi, Japan
fDate :
4/1/1997 12:00:00 AM
Abstract :
A precise null-balancing technique, which we call the PNB technique, has been developed for the 10 V Josephson-junction-array voltage standard system (10 V JJAVS) in order to improve the accuracy in null detection. Precision is achieved by (1) precisely capturing the desired Josephson step within ±3 step by using a newly developed mercury reed-relay switch, (2) adjusting the millimeter-wave frequency to attain strict null-balancing, and (3) using a stable chopper-type of digital voltmeter (DVM) as a null detector. This PNB technique was successfully applied to a 10 V JJAVS attaining a total uncertainty of 6×10-9 and reducing the calibration time to 20 min to 30 min
Keywords :
calibration; choppers (circuits); digital voltmeters; measurement standards; millimetre wave devices; reed relays; superconducting junction devices; voltage measurement; 10 V; 20 to 30 min; JJAVS; Josephson junction array voltage standard; PNB technique; calibration time; chopper digital voltmeter; mercury reed-relay switch; millimeter-wave frequency; null detection; null-balancing; uncertainty; Circuits; Detectors; Frequency; Josephson junctions; Laboratories; Millimeter wave technology; Scattering; Standards development; Switches; Voltage;
Journal_Title :
Instrumentation and Measurement, IEEE Transactions on
