The project successfully finished! All the publicly available results are summarized in Overview of results of the EMPIR project ACQ-PRO.
- Details
- Category: News and events
- Hits: 1165
The project or results of the project have been presented at following occasions:
- Raúl Caballero, El acceso a los patrones cuánticos de alterna. El proyecto ACQ-PRO, 6º Congreso español de metrología, June 2017, Spain
- Raúl Caballero, Los efectos cuánticos en la metrología de corriente alterna y la metrología digital., 6º Congreso español de metrología, June 2017, Spain
http://fr.calameo.com/read/0052381522d20d2edd696 - Yolanda Álvarez, Digital metrology and quntum standards: ACQ-PRO EMPIR Project, 22nd IMEKO TC4 international symposium, September 2017, Romania
- Paolo Durandetto, "Applications of AC Quantum Voltage Standards at PTB in the scope of the ACQ-PRO EMPIR project", QMSC 2017 - Quantum Metrology Students Conference, September 2017, Italy
- Paolo Durandetto, Josephson standards for a new AC quantum voltage infrastructure (in the scope of the ACQ-PRO EMPIR project), EUCAS 2017 - European Conference on Applied Superconductivity, September 2017, Switzerland
http://eucas2017.org/2017/scientific-program/
Presented poster can be downloaded here:
- Details
- Category: News and events
- Hits: 1959
The project was presented at technical comitee of Euramet: subcommitee for DC and Quantum Metrology and subcommitee for Low frequency. The content of presentations can be downloaded here. The leaflets distributed during commitee meetings can be downloaded here.
- Details
- Category: News and events
- Hits: 1343
BIPM, NPL and PTB comparison carried out as part of EMPIR project will be used to validate AC quantum voltage standard.
Thanks to the collaboration of BIPM in the project, a pioneering intercomparison of AC quantum voltage standards has been arranged and will start this year. The BIPM, NPL and PTB comparison will be used to validate the AC quantum voltage standard design. The design is based on the combination of a PJVS and ultra-stable synthesiser so different waveform can be compared. This will serve as a basis for future worldwide comparisons of AC quantum voltage standards.
This news was published also on EURAMET news site.
- Details
- Category: News and events
- Hits: 1322
An intercomparison of AC quantum standard have been proposed. The participants will be BIPM, NPL and PTB. As a transfer standard a DualDAC2 developed by MIKES and AIVON will be used. The comparison will take place in the first half of 2017. The uniqueness is quantum standards of all three participants are of unique and different design.
- Details
- Category: News and events
- Hits: 1518
A new technical comittee is being formed and will be proposed as a working group of Euramet TC-EM. The leader of the action is This email address is being protected from spambots. You need JavaScript enabled to view it. (INRIM). The objective is to establish the basis for the future European cooperation on AC voltage quantum standards.
Because the cooling systems are very important and diverse in quantum standards, a group related to cryogenics will be formed by This email address is being protected from spambots. You need JavaScript enabled to view it. (FCT-UNL).
If you are interrested, contact Andrea Sosso, This email address is being protected from spambots. You need JavaScript enabled to view it., or anyone from Impact Advisory Board.
- Details
- Category: News and events
- Hits: 1791
Martin Šíra from CMI (Czech Metrology Insittute) visited PTB (Physikalisch-Technische Bundesanstalt) for three monts, from August to October 2016, to study application of Josephson Arbitrary Waveform System for calibration of digitizers. A special waveform have been prepared with the aim of calibrating a number of digitizer parameters at once. Parameters of the waveform were based on the properties of the JAWS system in PTB. The waveform have been generated by JAWS using three different configurations of chips to get different range of waveform amplitudes. JAWS is the only device capable of generating such a waveform with sufficient precission and stability. The waveform was sampled by selected digitizers. After an extensive data processing of sampled data several digitizer parameters have been obtained and stability and correlation factors of these parameters was estimated.
Vitor Cabral from IPQ (Instituto Português da Qualidade) realized training visit in PTB from 17 to 28 of October 2016. The system setup used for the experimental work was an “AC quantum voltmeter” as a standard to calibrate directly an ac source. The reference system was formed by a PTB Josephson array of 10 V with 16 segments which were biased by a set of 4 commercial current sources. This setup forms a Programmable Josephson Voltage Standard which allows a generation of a stepwise sine wave. The source signal under calibration was compared to the Josephson voltage by a sampling process of the differential voltage measured by a commercial ADC. The measurements were conducted in the way to exploring different parameters configuration of the setup (as the sampling rate, number of periods averaged, number of deleted points in the step transitions) in order to observe the repeatability and/or reproducibility of the results, along its work range of voltage and frequency. These experimental work allowed the acquisition of practical knowledge in several operating features of the system as the: operation of the Josephson array by the control of the bias source associated; the way to check and recognize the happening of flux trapped and the process to deal with it, by the heating of the array; the process to measure and optimize the bias current to each segment of the array, the role of the different parameters configuration to define the measurement process and theirs influence in the measurement results.
Raúl Caballero Santos from CEM (Centro Español de Metrología) visited PTB. The visit was related with the frequency response and stability of Anolog–to-Digital Converters (ADC) using the PTB Josephson Array Waveform Synthesizer (JAWS). This activity has been very successful and the preliminary data obtained are very promising. This characterization will significantly improve the AC metrological application of the ADCs.
JAWS 1 in PTB laboratory is shown on follwing picture.
- Details
- Category: News and events
- Hits: 1551
The project have been presented on two technical subcommitees of Euramet: TC-EM DC and Quantum Metrology and Power and Energy. The presentation can be downloaded here.
- Details
- Category: News and events
- Hits: 1538
From 11 to 22 of april another research visit occured. Vitor Cabral from IPQ (Instituto Português da Qualidade) visited NPL (National Physical Laboratory, United Kingdom) and studied Josephson Voltage Systems. The system setup used for the experimental work was a “quantum-referenced waveform synthesizer” as a standard to calibrate directly a Voltmeter. The reference system was formed by a Josephson array of 1 V biased by a current source developed by NPL. As transfers standards was used a commercial DAC that was compared to the Josephson voltage by a sampling process of the differential voltage measured by commercial ADC. The signal of the referenced DAC was used as standard signal to be measured by a DATRON 4920 Voltmeter. The measurements were conducted in the way to exploring different configurations of the setup, equipment and/or measurements conditions in order to observe the repeatability and/or reproducibility of the results. These experimental work allowed the acquisition of practical knowledge in several operating features of the system as the: operation of the Josephson array by the control of the bias source associated; the way to check and recognize the happening of flux trapped and the process to deal with it, by the heating of the array; the major role of the control of the synchronism between the different signals to assure the observation of valid data; the influence in the results of the sampling time instant related to its position in the step of the voltage array; the dependence of the system to the interconnections used and to the consequent current flow.
Javier Díaz de Aguilar Rois from CEM (Centro Español de Metrología) visited NPL. The visit was mainly related on the feasibility of an ac source based on Digital-to-Analog-Converter (DAC) directly corrected by a Programable Josephson Voltage Standard (PJVS). The initial characterization of the system shows the improvement of the incorporation an ultrastable DAC on the system. More work is necessary but preliminary results are very promising to use this configuration as a new standard. This new standard can be also used for the intercomparison of AC quantum standards.
ACJVS in NPL laboratory is shown on follwing picture.
- Details
- Category: News and events
- Hits: 1681
In January and February 2016 first ACQ-PRO research visits occurred. Adam Tatar from GUM (Główny Urząd Miar, Poland) and Recep Orhan from TÜBİTAK (TÜRKİYE BİLİMSEL ve TEKNOLOJİK ARAŞTIRMA KURUMU, Turkey) visited NPL (National Physical Laboratory, United Kingdom) where under the guidance of Jonathan Williams several experiments and measurements were conducted. System used by researchers was based on 1 V Josephson junctions array made in AIST (National Institute of Advanced Industrial Science and Technology, 産業技術総合研究所, Japan) and binary bias source designed and build in NPL. The SNS array of 32 767 junctions was used to generate DC signal of maximum voltage 1.08 V and sinewaves of maximum voltage 0.76 V RMS. During the visit researchers checked and calibrated bias source and made precise current/voltage measurements of Shapiro steps – its width and step centre. Different AC quantum voltages were generated. Stable filtered DAC sinewave compared with quantum sinewave was used for AC/DC transfer which was made with Datron 4920 multimeter. A Shapiro steps are shown on following figures.
- Details
- Category: News and events
- Hits: 1609
First public result of the project is the Collection of training materials. This collection gives an insight into the problem of AC josephson standards, its applications and cooling techiques. The link to the document is in article Collection of training materials.
- Details
- Category: News and events
- Hits: 1435
A sharepoint for exchange of documents between JRP partners was established by NPL at website https://shared.npl.co.uk/acq-pro/ .
- Details
- Category: News and events
- Hits: 1417
Impact Advisory board was established.
The board will provide advice and assistance to direct the work and impact in the ACQ-PRO project. You are welcome to contact the board in the case of suggestion, questions, problems, doubts or ideas.
Members of the board are:
Luis Palafox
PTB, Germany
This email address is being protected from spambots. You need JavaScript enabled to view it.
Helge Malmbekk
JV, Norway
This email address is being protected from spambots. You need JavaScript enabled to view it.
Martin Šíra
CMI, Czech Republic
This email address is being protected from spambots. You need JavaScript enabled to view it.
Jonathan Williams
NPL, United Kingdom
This email address is being protected from spambots. You need JavaScript enabled to view it.
- Details
- Category: News and events
- Hits: 2249
The kick-off meeting will be held in PTB, Braunschweig, Germany from 22. 6. 2015 to 26. 6. 2015. During the meeting Workshop on quantum based voltage measurements will be held.
The agenda of the workshop:
- Details
- Category: News and events
- Hits: 1600
The project ACQ-PRO has been successfully funded and started 1. 6. 2015
- Details
- Category: News and events
- Hits: 1497