Title :
Low-noise measurements of the quantized Hall resistance using an improved cryogenic current comparator bridge
Author :
Delahaye, F. ; Bournaud, D.
Author_Institution :
Bur. Int. des Poids et Mesures, Sevres, France
Abstract :
Significant improvements have been made on the bridge based on a cryogenic current comparator (CCC bridge) that is used at the Bureau International des Poids et Mesures, France (BIPM), for measurements of the quantized Hall resistance (QHR). Specifically, a SQUID (superconducting quantum interference device)-based DC nanovoltmeter and a new CCC with an increased number of turns have been built and incorporated into the bridge. QHR measurements with a very low noise level (2 parts in 10/sup 9/ of the ratio of the QHR to a 100- Omega standard) have been carried out using this improved bridge.<>
Keywords :
SQUIDs; bridge instruments; electric resistance measurement; low-temperature techniques; measurement standards; quantum Hall effect; voltmeters; BIPM; Bureau International des Poids et Mesures; France; SQUID; cryogenic current comparator bridge; low noise measurement; nanovoltmeter; quantized Hall resistance; superconducting quantum interference device; Bridges; Cryogenics; Current measurement; Electrical resistance measurement; Interference; Nanoscale devices; Noise measurement; SQUIDs; Superconducting device noise; Superconducting devices;
Conference_Titel :
Precision Electromagnetic Measurements, 1990. CPEM '90 Digest., Conference on
Conference_Location :
Ottawa, Ontario, Canada
DOI :
10.1109/CPEM.1990.110033
