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We have evaluated the linearity of commercial digital voltmeters (DVMs) using a programmable Josephson voltage standard (PJVS) system. The PJVS system is composed of a 524 288-niobium nitride-based Josephson junction array that has the ability to generate arbitrary output voltages up to 17 V with a resolution of 12 bits. In our system, the junction array is operated in a 10-K compact cooler without...
The high-voltage DC measuring system based on bandgap voltage references has been used for high accuracy with low dynamic resistance up to 20 kV. The measuring system is stable output over a wide range of operating current and ambient temperature, and it is insensitive to effects due to leakage currents. One of the most important parameters of a reference system is its long-term stability. This paper...
We describe a method to identify and correct slowly decaying transients in electrical measurements which are performed with periodic reversal of current or voltage bias. Such transients may be of different physical origin like, e.g., dielectric absorption in insulators, which often exhibit a 1/t time dependence, or the Peltier effect. We demonstrate the method with data collected in precision resistance...
This paper describes the procedure, data processing and results in capacitance measurements using indirect method, deriving the quantity from voltage, electric current and capacitor's charge time. Results obtained with DMM HP 3458A, Agilent 3458A y Fluke 8508A are described.
Recent improvements on the ECCS experiment at PTB are reported. A 5-junction single-electron R-pump is shown to shuttle electrons with a relative transfer error of 5×10−8. Moreover, the relative uncertainty of the setup for the cryogenic capacitor voltage measurement has been reduced to urel < 10−9. Further perspectives related to data evaluation and analysis on the ECCS experiment is also...
This paper describes the development of a quantum waveform synthesizer operating at a sampling frequency of 100 kHz with the aim of generating sine waves directly traceable to the Josesphson quantum voltage standard. The quantum reference is based on arrays of 65 536 Josephson junctions, fabricated using Nb/TiN/Nb technology and operating at a bias frequency of 16 GHz corresponding to an output voltage...
This article presents experimental evidence for a very low bias current dependence on the fundamental component for a sum of square wave signals synthesized by a Programmable Josephson Voltage Standard (PJVS). The typical bias current dependence due to the transients can be suppressed, as has been theoretically predicted [1]. Measurements show that the sum of square wave signals has a slope of less...
Possibilities and limitations of using measurement system based on two sampling multimeters (DVM) for the ratio measurement of two impedances was investigated in MIKES. Calibration of a 1 µF capacitor from the quantized Hall resistance (QHR) was made at low frequencies. A frequency dependence of ceramic 1 µF capacitor in frequency range 12 Hz – 1600 Hz was measured against different reference resistors...
The CENAM Josephson Voltage Standard (JVS) was purchased in 1994. During its 18 years of use, several improvements have allowed to reduce noise immunity, measurements dispersion and uncertainty. During this period we participated in several international comparisons, the results show the improvements of the JVS. The current combined uncertainty of the CENAM JVS is 1.3 nV as a DC voltage measurement...
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