Quantum Hall Effect Resistance Standards Research Articles

Current Status of Quantum Hall System Implantation at the Inmetro

This paper presents the activities currently being performed at the Inmetro with a view to obtaining the international recognition of its quantum Hall system as the primary standard of electrical resistance in Brazil. To enable it, the Inmetro is making arrangements to take part in the ongoing key comparison BIPM.EM-K12, which is an on-site comparison of quantum Hall effect resistance standards. Besides, as a prerequisite for joining in this key comparison, Inmetro is participating in the ongoing key comparison BIPM.EM-K13.a&b.

On-site comparison of Quantum Hall Effect resistance standards of the NMC A*STAR and the BIPM: Ongoing key comparison BIPM.EM-K12

Main textThe ongoing on-site comparison BIPM.EM-K12 is part of the BIPM programme implemented to verify the international coherence of the primary resistance standards. It allows National Metrology Institutes (NMIs) to validate their implementations of the Quantum Hall Effect (QHE) for dc resistance traceability by comparison to the reference maintained at the BIPM.The realization of the ohm from the QHE-based standard of the NMIs at 100 Ω is compared with that realized by the BIPM from its own transportable quantum Hall resistance standard. This comparison is usually completed by scaling measurements from 100 Ω to 1 Ω and 10 kΩ through the measurement of the resistance ratios 100 Ω/1 Ω and 10 kΩ/100 Ω, respectively.In March 2019, a new BIPM.EM-K12 on-site comparison was carried out at the National Metrology Centre, NMC A*STAR (Singapore). It was the first time the NMC A*STAR participated in this comparison programme. Only the measurement results of the 100 Ω based on the quantum Hall effect and of the 10 kΩ/100 Ω ratio are presented in the report. The reason why the results of the 100 Ω/1 Ω ratio were not included is explained in the introduction of the report.Measurements of the 100 Ω transfer standard in terms of the SI value of the von Klitzing constant, R K, agreed to 1.6 parts in 109 with a relative combined standard uncertainty u c = 3.3 × 10−9. Measurements of 10 kΩ/100 Ω ratio agreed to 2.0 parts in 109 with u c = 2.8 × 10−9.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of Quantum Hall Effect resistance standards of the NMIJ-AIST and the BIPM: Ongoing key comparison BIPM.EM-K12

The ongoing on-site comparison BIPM.EM-K12 is part of the BIPM programme implemented to verify the international coherence of the primary resistance standards. It allows National Metrology Institutes (NMIs) to validate their implementations of the Quantum Hall Effect (QHE) for dc resistance traceability by comparison to the reference maintained at the BIPM.The realization of the ohm from the QHE-based standard of the NMIs at 100 Ω is compared with that realized by the BIPM from its own transportable quantum Hall resistance standard. This comparison is usually completed by scaling measurements from 100 Ω to 1 Ω and 10 kΩ through the measurement of the resistance ratios 100 Ω/1 Ω and 10 kΩ/100 Ω, respectively.In November 2018, a new BIPM.EM-K12 on-site comparison was carried out at the National Metrology Institute of Japan (NMIJ-AIST). It was the first time the NMIJ-AIST participated in this comparison programme.In the present comparison, only the measurements of the 100 Ω based on the quantum Hall effect and of the 10 kΩ/100 Ω ratio were compared. The reason why the 100 Ω/1 Ω ratio was not measured is detailed in the report.Measurements of the 100 Ω transfer standard in terms of the conventional value of the von Klitzing constant, R K-90, agreed to 1.8 parts in 109 with a relative combined standard uncertainty u c = 8.7 × 10−9. Measurements of 10 kΩ/100 Ω ratio agreed to 6.8 parts in 109 with u c = 8.3 × 10−9.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of quantum Hall effect resistance standards of the NIM and the BIPM: ongoing key comparison BIPM.EM-K12

The ongoing on-site comparison BIPM.EM-K12 is part of the BIPM programme implemented to verify the international coherence of the primary resistance standards. It allows National Metrology Institutes (NMIs) to validate their implementations of the quantum Hall effect (QHE) for dc resistance traceability by comparison to the reference maintained at the BIPM.The realization of the ohm from the QHE-based standard of the NMIs at 100 Ω is compared with that realized by the BIPM from its own transportable quantum Hall resistance standard. This comparison is usually completed by scaling measurements from 100 Ω to 1 Ω and 10 kΩ through the measurement of the resistance ratios 100 Ω/1 Ω and 10 kΩ/100 Ω, respectively.In September 2019, a new BIPM.EM-K12 on-site comparison was carried out at the National Institute of Metrology of China (NIM). It was the first time the NIM participated in this comparison programme.Measurements of the 100 Ω transfer standard in terms of the SI value of the von Klitzing constant, R K, agreed to 4 parts in 1010 with a relative combined standard uncertainty u c = 26 × 10−10. Measurements of 10 kΩ/100 Ω and 100 Ω/1 Ω ratios agreed to 50 parts in 1010 with u c = 24 × 10−10 and to 10 parts in 1010 with u c = 23 × 10−10, respectively.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of quantum Hall effect resistance standards of the KRISS and the BIPM: ongoing key comparison BIPM.EM-K12

The ongoing on-site comparison BIPM.EM-K12 is part of the BIPM programme implemented to verify the international coherence of the primary resistance standards. It allows National Metrology Institutes (NMIs) to validate their implementations of the quantum Hall effect (QHE) for dc resistance traceability by comparison to the reference maintained at the BIPM.The realization of the ohm from the QHE-based standard of the NMIs at 100 Ω is compared with that realized by the BIPM from its own transportable quantum Hall resistance standard. This comparison is usually completed by scaling measurements from 100 Ω to 1 Ω and 10 kΩ through the measurement of the resistance ratios 100 Ω/1 Ω and 10 kΩ/100 Ω, respectively.In October 2019, a new BIPM.EM-K12 on-site comparison was carried out at the Korea Research Institute of Standards and Science (KRISS). It was the first time the KRISS participated in this comparison programme.Measurements of the 100 Ω transfer standard in terms of the SI value of the von Klitzing constant, R K, agreed to 4 parts in 1010 with a relative combined standard uncertainty u c = 24 × 10−10. Measurements of 10 kΩ/100 Ω and 100 Ω/1 Ω ratios agreed to 8 parts in 1010 with u c = 26 × 10−10 and to 2 parts in 1010 with u c = 23 × 10−10, respectively.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of Quantum Hall Effect resistance standards of the NRC-CNRC and the BIPM: ongoing key comparison BIPM.EM-K12

The ongoing on-site comparison BIPM.EM-K12 is part of the BIPM programme implemented to verify the international coherence of the primary resistance standards. It allows National Metrology Institutes (NMIs) to validate their implementations of the Quantum Hall Effect (QHE) for dc resistance traceability by comparison to the reference maintained at the BIPM.In this comparison, the realization of the ohm from the QHE-based standard of the NMIs at 100 Ω is compared with that realized by the BIPM from its own transportable quantum Hall resistance standard. This comparison is completed by scaling measurements from 100 Ω to 1 Ω and 10 kΩ through the measurement of the resistance ratios 100 Ω/1 Ω and 10 kΩ/100 Ω, respectively.In June 2018 a new BIPM.EM-K12 on-site comparison was carried out at the National Research Council Canada (NRC-CNRC). It was the first time the NRC-CNRC participated in this comparison program.Measurements of the 100 Ω transfer standard in terms of the conventional value of the von Klitzing constant, RK-90, agreed to 5 parts in 1010 with a relative combined standard uncertainty u c = 23 × 10-10. Measurements of 10 kΩ/100 Ω and 100 Ω/1 Ω ratios agreed to 13 parts in 1010 with u c = 21 × 10-10 and to 1 part in 1010 with u c = 40 × 10-10, respectively.KEY WORDS FOR SEARCHQuantum Hall Effect, key comparison, resistance standard, resistance ratioMain textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of Quantum Hall Effect resistance standards of METAS and the BIPM: Ongoing key comparison BIPM.EM-K12

An on-site comparison of the quantum Hall effect (QHE) resistance standards of the Federal Institute of Metrology METAS (Switzerland) and of the Bureau International des Poids et Mesures (BIPM) was made in December 2017. Measurements of a 100 Ω standard in terms of the conventional value of the von Klitzing constant, R K-90, agreed to 5 parts in 1010 with a relative combined standard uncertainty u c = 23 × 10−10.Scaling from 100 Ω to 10 kΩ has also been addressed through the measurement of a 10000 Ω/100 Ω ratio. The measurements carried out agreed to 2 parts in 1010 with a relative combined standard uncertainty u c = 19 × 10−10.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

On-site comparison of Quantum Hall Effect resistance standards of the CMI and the BIPM: ongoing key comparison BIPM.EM-K12

An on-site comparison of the quantum Hall effect (QHE) resistance standards of the Czech Metrology Institute (CMI) and of the Bureau International des Poids et Mesures (BIPM) was made in April 2017. Measurements of a 100 Ω standard in terms of the conventional value of the von Klitzing constant, R K-90, agreed to 6 parts in 1010 with a relative combined standard uncertainty u c = 25 × 10−10. Measurements of 10000 Ω/100 Ω and 100 Ω/1 Ω ratios agreed to 11 parts in 1010 with u c = 22 × 10−10 and to 33 parts in 1010 with u c = 32 × 10−10, respectively. The influence of the current reversal time has been systematically investigated in order to take into account possible errors due to the Peltier effect, which may be particularly large in 1 Ω standards.Main textTo reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Behavior of 1 Ω resistors at frequencies below 1 Hz and the problem of assigning a dc value

This paper presents a systematic study of the effects of reversals of current polarity on 1 Ω standard resistors. A selection of 1 Ω standards were measured on a dc cryogenic current comparator bridge and also on an ac current comparator bridge operating at 1 Hz. We find that the apparent 4 terminal resistance depends strongly on the dc reversal rate, in one case showing a variation of more than 0.1 μΩ/Ω for cycle times between 10 s and 1000 s. Even in the best cases, effects of at least 0.01 μΩ/Ω are present. Furthermore, the assumption that the apparent resistance value converges to a limiting value for long waiting times after reversal is not always upheld, making it difficult to quote a simple dc value. Existing models of Peltier heating at wire junctions do not completely explain our observations. The problems presented have been the limiting factor for 1 Ω measurements as part of a recent on-site comparison of quantum Hall effect resistance standards.

Room-Temperature Quantum Hall Effect in Graphene

The quantum Hall effect (QHE), one example of a quantum phenomenon that occurs on a truly macroscopic scale, has attracted intense interest since its discovery in 1980 and has helped elucidate many important aspects of quantum physics. It has also led to the establishment of a new metrological standard, the resistance quantum. Disappointingly, however, the QHE has been observed only at liquid-helium temperatures. We show that in graphene, in a single atomic layer of carbon, the QHE can be measured reliably even at room temperature, which makes possible QHE resistance standards becoming available to a broader community, outside a few national institutions.

Comparison of quantum Hall effect resistance standards of the NIST and the BIPM

An on-site comparison of the quantum Hall effect (QHE) resistance standards of the National Institute of Standards and Technology (NIST) and of the Bureau International des Poids et Mesures (BIPM) was made in April 1999. Measurements of a 100 Ω standard in terms of the conventional value of the von Klitzing constant, RK-90, agreed to 12 parts in 1010 with a relative combined standard uncertainty uc = 20 × 10-10. Measurements of 10 000 Ω/100 Ω and 100 Ω/1 Ω ratios agreed to 59 parts in 1010 with uc = 55 × 10-10 and to 38 parts in 1010 with uc = 31 × 10-10, respectively.

Comparison of quantum Hall effect resistance standards of the PTB and the BIPM

An on-site comparison of the quantum Hall effect (QHE) resistance standards of the PhysikalischTechnische Bundesanstalt (PTB) and of the Bureau International des Poids et Mesures (BIPM) was made in October 1995. Measurements of a 100 Ω standard in terms of RH(2), the quantized resistance corresponding to the quantum number 2, agreed to -5,5 parts in 1010 with a relative combined standard uncertainty uc = 19 × 10-10. Measurements of 10 000 Ω/100 Ω and 100 Ω/1 Ω ratios agreed to -4 parts in 1010 with uc = 19 × 10-10 and 12 parts in 1010 with uc = 26 × 10-10, respectively.

Comparison of quantum Hall effect resistance standards of the OFMET and the BIPM

An on-site comparison of the quantum Hall effect (QHE) resistance standards of the Swiss Federal Office of Metrology (OFMET) and of the Bureau International des Poids et Mesures (BIPM) was made in November 1994. Measurements of a 100 Ω standard in terms of RH(2), the quantized resistance corresponding to the quantum number 2, agreed to (9 ± 17) parts in 1010. Measurements of 10 000 Ω/100 Ω and 100 Ω/1 Ω ratios agreed to (0,8 ± 18) parts in 1010 and (7,5 ± 27) parts in 1010, respectively.

Comparison of quantum Hall effect resistance standards of the BNM/LCIE and the BIPM

A comparison of quantum Hall effect (QHE) resistance standards has been carried out by taking a complete QHE system from the BIPM to the Laboratoire Primaire d'Electricite-Magnetisme (BNM/LCIE). From December, 14-17, 1993, measurements of the same 100 /spl Omega/ standard resistor were carried out in terms of the quantized Hall resistance (QHR) standards of the two laboratories. This exercise followed a preliminary comparison in July 1993 in which the ratio of the 100 /spl Omega/ standard to a 1 /spl Omega/ standard, and that of the 100 R standard to a 10 k/spl Omega/ standard were measured at the BNM/LCIE using the resistance-ratio bridges of both laboratories. All comparison results agree to within 4 parts in 10/sup 9/. In particular, the values attributed by the two laboratories to the 100 R standard, based on the mean of measurements made on the i=2 plateaus of GaAs-based heterostructures, agreed to (1.2/spl plusmn/3.0) parts in 10/sup 9/. >