Direct comparison between a programmable and a conventional Josephson voltage standard at the level of 10 V

Abstract

A Josephson voltage standard (JVS) from the BIPM, incorporating a PTB 10 V programmable array, has been compared with a JVS from the LNE, operating with a conventional hysteretic array. The metrological characteristics of both JVSs were carefully studied. We report on the experiments performed for this comparison and on the uncertainty components. The final comparison result is (U PJVS − U JVS )/ U JVS = −3.2 × 10 −11 with a relative total combined standard uncertainty of 6.1 × 10 −11 (k = 1).

Single-Chip 10-V Programmable Josephson Voltage Standard System Based on a Refrigerator and Its Precision Evaluation

“…Within the uncertainty, the PJVS agreed with the CJVS (V MEAS − V PJVS = 1.1 nV). This implies that the CCR-based 10-V PJVS shows sufficiently low uncertainty, similar to that of the liquid-helium-based CJVS system [12], [15]. 2 …”

“…The use of the CCR has the potential to increase the popularity of PJVS systems not only as primary standards but also as secondary standards or for quality control at construction sites. To date, the operation of a 10-V PJVS based on liquid-helium cooling has been demonstrated [3], [6], [12]; however, a PJVS based on the CCR is more preferable. Unlike liquid-helium cooling, difficulty with the thermal link between the chip and the coldhead of the refrigerator is a bottleneck.…”

Conception et applications d’un étalon Josephson programmable de 1 V au LNE

“…L'incertitude combinée tient compte des composantes d'incertitude associées à la fréquence micro-onde, au détecteur de zéro et aux résistances de fuites [8,17]. Ces résultats démontrent que le nouveau système peut être utilisé comme référence primaire de tension continue par le laboratoire d'étalonnage électrique.…”

“…Et plus récemment, une comparaison directe entre le LNE et le Bureau international des poids et mesures (BIPM) a montré un très bon accord à 10 V [17], démontrant une différence relative (U RJJP − U RJJC )/U RJJC de −3,2 × 10 −11 associée à une incertitude type relative u c /U LNE de 6,1 × 10 −11 .…”

Direct Comparison of Josephson Voltage Standards at 10 V Between BIPM and CENAM

“…Some laboratories calibrate the frequency of their microwave source and reach a frequency uncertainty of 1 Hz (0.08 nV at 10 V). The BIPM measured the frequency of their microwave system (Gunn diode, EIP counter and frequency stabilizer) using a heterodyne method and claims a frequency uncertainty of 0.1 Hz (8 pV) [3]. The measurement dispersion that is possible to obtain with the best commercial nanovoltmeters is of the order of a few tenths of a nV.…”