SLIDE 1
Achievements in the quantum electrical effects
- CCEM report
Dr.ir. Gert Rietveld CCEM President
- Dr. Michael Stock
CCEM Executive Secretary
CCEM/19-03_c
2 www.bipm.org
Achievements in the quantum electrical effects - CCEM report - - PowerPoint PPT Presentation
Achievements in the quantum electrical effects - CCEM report - - PowerPoint PPT Presentation
CCEM/19-03_c Achievements in the quantum electrical effects - CCEM report Dr.ir. Gert Rietveld CCEM President Dr. Michael Stock CCEM Executive Secretary Electrical measurements in daily life Sustainable Telecom society Nanoelectronics
SLIDE 2
SLIDE 3
3 www.bipm.org
The ampere will never be better than the IPK
CCEM scientific challenge
is to improve this!
Present definition of the ampere
“The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in vacuum, would produce between these conductors a force equal to 2 × 10−7 Newton per metre of length.”
SLIDE 4
4 www.bipm.org
Key objective: advise CIPM on electromagnetic metrology 25 members Meetings: 2015, 2017 WGLF + GTRF, WGRMO WGKG, WGSI: preparations for the revised SI!
Introducing the CCEM community
Scientific presentations on graphene, waveform metrology, ampere Workshop on future EM challenges (2017) and on microwave measurements (2019)
SLIDE 5
5 www.bipm.org
Conventional 1990 values Link to SI “only at 10−7 level”, internal agreement at < 10−9 level Recent developments: AC JAVS, QHE in graphene
Global forum for progressing the state-of-the-art
V = n (h/2e) f R = (h/e2) 1/n KJ-90 RK-90
Quantum standards for voltage and resistance:
SLIDE 6
6 www.bipm.org
Control of single electrons
basis for new ampere
definition!!
Quantum current standard: Single Electron Transport
Courtesy PTB Courtesy NIST
SLIDE 7
7 www.bipm.org
Single Electron Transport – recent progress
1995 2000 2005 2010 2015 2020 10
- 8
10
- 7
10
- 6
10
- 5
10
- 4
10
- 3
10
- 2
SAW SINIS GaAs Si KRISS
Relative Accuracy Uncertainty Year accuracy ~ 2x10-7
Courtesy KRISS Courtesy PTB
SLIDE 8
8 www.bipm.org
Kibble balance – paving the way to the revised SI
Combining 2 steps:
1.
Weighing: Mg = BLIw
2.
Moving: Vm = vBL Comparing electrical and mechanical Watt:
Josephson, QHE: V h/2e, R h/e2
h
w m I
V v g M =
Courtesy NRC
SLIDE 9
9 www.bipm.org
By fixing values of h and e, CCEM will be “back in the SI” However… Final values of h, e do not perfectly align with 1990 values
CCEM will be the only CC with a step change!
+0.107 ppm in voltage +0.018 ppm in resistance
Impact of the revised SI on EM quantities
1 10−9 1 10−7 Courtesy BIPM
SLIDE 10
10 www.bipm.org
Knowledge transfer to industry in making and operating quantum standards Revised SI support
Facilitating dialogue NMIs and stakeholders
Other ‘outreach’ activities: Future challenges workshop Support for CCRI
https://www.bipm.org/utils/common/pdf/CC/CCEM/ccem_guidelines_revisedSI.pdf
SLIDE 11
11 www.bipm.org
Quantum standards and 1990 conventional values of RK and KJ greatly increased EM measurement comparability worldwide CIPM MRA was a significant second step in enhancing worldwide acceptance of measurement results Concluding step: increased MRA efficiency BIPM provides crucial support to CCEM:
- n-site comparison of quantum standards,
calibration services, efficient performance
- f other comparisons (e.g. capacitance)
Global comparability of measurements
1 10−9
−7
SLIDE 12
12 www.bipm.org
CCEM is continuously working on its key objectives via
Advancing measurement science:
– Quantum Technologies – Bio- and nanoscience – Applied science for societal challenges (e.g. energy)
Enhancing impact to society:
pick up new challenges, increased stakeholder interaction
Increased comparability of measurement results:
versatile quantum standards ‘run’ the CIPM MRA as smoothly and effectively as possible
Summary
SLIDE 13
13 www.bipm.org
Precise measurements and quantum electrical effects
h / 2e e h / e2 V I R
SLIDE 14
www.bipm.org