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Traceable precision pA direct current measurements with the ULCA [article]

Hansjörg Scherer, Gerd-Dietmar Willenberg, Dietmar Drung, Martin Götz, Eckart Pesel
2014 arXiv   pre-print
Its amplifier stages, based on resistor networks and op-amps, can be calibrated traceably with a cryogenic current comparator (CCC) system.  ...  We find agreement between both methods at an uncertainty level below 10 microA/A, limited by the uncertainty of the currents generated with the capacitor charging method.  ...  The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.  ... 
arXiv:1407.5508v2 fatcat:hlcbcydu7ffurbahs24zn3hjqq

Characteristics of precision 1 Ω standard resistors influencing transport behaviour and the uncertainty of key comparisons

G R Jones, B J Pritchard, R E Elmquist
2009 Metrologia  
We have studied the effects of temperature, barometric pressure, humidity, power loading and heat dissipation in oil on transportable wire-wound 1 resistance standards that are based on different alloys  ...  We show that the relative standard uncertainty related to transport can be less than 0.01 µ −1 when using certain resistors of these two types that are characterized and selected for stability.  ...  Acknowledgment The authors wish to thank Dr Thomas J Witt for many helpful comments on the manuscript.  ... 
doi:10.1088/0026-1394/46/5/015 fatcat:m53jn64mhbgfjotknsej7bwgcq

Graphene surpasses GaAs/AlGaAs for the application of the quantum Hall effect in metrology [article]

R. Ribeiro-Palau, F. Lafont, J. Brun-Picard, D. Kazazis, A. Michon, F. Cheynis, O. Couturaud, C. Consejo, B. Jouault, W. Poirier, F. Schopfer
2015 arXiv   pre-print
of versatile and user-friendly quantum standards, compatible with a broader industrial use.  ...  In particular, in the device presented here, the Hall resistance is accurately quantized within 1× 10^-9 over a 10-T wide range of magnetic field with a remarkable lower bound at 3.5 T, temperatures as  ...  The room-temperature resistor used in the indirect comparison of R H-G and R H-GaAs is a 100- resistor (TEGAM) of resistance R 100 .  ... 
arXiv:1504.06511v1 fatcat:5p2w7s25dzdlpaqdzskeuvxhki

Transport behavior of commercially available 100-Ω standard resistors

B. Schumacher, P. Warnecke, W. Poirier, I. Delgado, Z. Msimang, G. Boella, P.O. Hetland, R.E. Elmquist, J. Williams, D. Inglis, B. Jeckelmann, O. Gunnarsson (+1 others)
2001 IEEE Transactions on Instrumentation and Measurement  
Several types of commercial 100-resistors can be used with the cryogenic current comparator to maintain the resistance unit, derived from the quantized Hall effect (QHE), and to disseminate this unit to  ...  A constant drift model has been applied, and the results are evaluated in such a way that the transport properties of these resistors are treated independently for the different types of resistor.  ...  ACKNOWLEDGMENT The authors thank NPL, Tegam, and ZIP for kindly supplying resistors for this project.  ... 
doi:10.1109/19.918112 fatcat:tt2u76stz5hrvnry265dwthr3e

News from the BIPM laboratories—2017

Steven Judge, Patrizia Tavella, Felicitas Arias, José María Los Arcos, Michael Stock, Robert Wielgosz, Martin Milton
2018 Metrologia  
These laboratories act as centres for scientific and technical collaboration between Member States providing capabilities for international measurement comparisons on a sharedcost basis.  ...  They coordinate international comparisons of national measurement standards agreed to be of the highest priority, and they establish and maintain appropriate reference standards for use as the basis of  ...  For these comparisons, the BIPM QHR equipment, including the cryostat with the magnet and the quantum Hall sample, a resistance comparison bridge and thermo-regulated resistors of 1 , 100 and 10 k  ... 
doi:10.1088/1681-7575/aaa48d fatcat:wcd37xyfoffi5aks635lsf2nku

The watt or Kibble balance: a technique for implementing the new SI definition of the unit of mass

Ian A Robinson, Stephan Schlamminger
2016 Metrologia  
A number of Kibble balances have either been built or are under construction and we compare the principal features of these balances.  ...  The redefinition of the SI unit of mass in terms of a fixed value of the Planck constant has been made possible by the Kibble balance, previously known as the watt balance.  ...  Acknowledgement Parts of the article are contributions of the US Government and therefore those parts are not subject to copyright in the USA/Contribution of NPL.  ... 
doi:10.1088/0026-1394/53/5/a46 pmid:35023879 pmcid:PMC8752041 fatcat:rv5eqgynijcpbbxbasgcvnkixu

The Performance of the KIBB-g1 Tabletop Kibble Balance at NIST [article]

Leon Chao, Frank Seifert, Darine Haddad, Jon Pratt, David Newell, Stephan Schlamminger
2019 arXiv   pre-print
A tabletop-sized Kibble balance (KIBB-g1) designed to directly realize mass at the gram-level range with uncertainties on the order of parts in 10^6 has been developed at the National Institute of Standards  ...  The masses of a nominally 5 g and 1 g weight were determined with 1-σ standard uncertainties of 9.0 g and 6.7 g, respectively. The corresponding relative uncertainties are 1.8× 10^-6 and 6.3× 10^-6.  ...  ACKNOWLEDGMENT The authors would like to thank Shisong Li for the magnet design, Alireza Panna for the resistor calibration, Bryan Waltrip and Mike Berilla for the current source design, Stefan Cular for  ... 
arXiv:1910.09218v1 fatcat:irvtrm5n3vaupb6hugdhjdplte

Quantum resistance metrology using graphene

T J B M Janssen, A Tzalenchuk, S Lara-Avila, S Kubatkin, V I Fal'ko
2013 Reports on progress in physics (Print)  
We also brie y discuss progress in the two other graphene material systems, exfoliated graphene and chemical vapour deposition graphene, and make a critical comparison with SiC graphene.  ...  We mainly focus our review on graphene expitaxially grown on SiC, a system which so far resulted in the best results.  ...  value in terms of a room temperature 100 resistor with a CCC bridge described in the section 3.1.  ... 
doi:10.1088/0034-4885/76/10/104501 pmid:24088373 fatcat:2b5pegicvrcdthqow7grbddvvm

The progress in development of the Planck-Balance 2 (PB2): A tabletop Kibble balance for the mass calibration of E2 class weights

Suren Vasilyan, Norbert Rogge, Christian Rothleitner, Shan Lin, Ivan Poroskun, Dorothea Knopf, Frank Härtig, Thomas Fröhlich
2021 TM. Technisches Messen  
of weights in the range from 1 mg to 100 g within the required uncertainties as stated by OIML recommendation R111 for weights of E2 class.  ...  We describe the design and the operational performance of the PB2 system in detail, the results of rigorous investigations of the error sources and subsequent improvements made since the beginning of the  ...  and the voltage drop over a precision resistor against the programmable Josephson voltage standard (PJVS) and the quantum Hall resistor (QHR) [3] .  ... 
doi:10.1515/teme-2021-0101 fatcat:7445nj7eebg63kptcaeltzz2gq