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News of the Year

Scientific Divisions

The International System of Units (SI) is to be fundamentally reformed. In future, the SI will be determined by seven defining constants, among them Planck’s constant h and the elementary charge e. The base units the kilogram and the ampere, which are currently defined via an artifact (in the case of the kg) or via an idealized measurement instruction (in the case of the ampere), can then also be...

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The kilogram

For the redefinition and realization of the kilogram via fundamental constants, PTB is pursuing, within the scope of the international Avogadro Project, an approach by “counting” atoms in isotopically enriched silicon single-crystals using the so-called “Xray Crystal Density (XRCD) method”.

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The ampere

Prototype of a self-referenced quantum current source developed at PTB with four semiconductor single-electron current sources (“single-electron pumps“) connected in series and three metallic singleelectron detectors.

In the new SI, the base unit the ampere is directly realized with quantum current sources which generate a single-electron current I at a frequency f : I = ef. PTB is developing a so-called self-referenced quantum current source.

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The second

Pre-cooled Sr atomic cloud with a temperature of a few millikelvin. After the temperature of the atoms had been reduced by a further factor of 1000 by means of laser cooling with red light, they serve as a reference in the lattice clock of PTB.

Since the redefinition of the second in the SI in 1967, the primary cesium atomic clocks, which realize the unit of time, the second, have become more exact by approximately one order of magnitude in each decade. Recently, however, the reproducibility and the stability of optical atomic clocks have become superior to the best cesium atomic clocks by orders of magnitude. In the case of these...

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Traceability relations in dimensional metrology

PTB is a member of EURAMET, the European Association of National Metrology Institutes. One of EURAMET’s essential goals is to provide an efficient, internationally competitive metrological infrastructure. A wide range of activities exist within EURAMET which are designed to meet this goal. One activity consists in having institutes trace certain measurands and measuring ranges to institutes in...

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Activity in a horizontal layer in the brain, exclusively in the area of the auditory cortex; the different colors show stimulus frequencies ranging from 8 Hz to 250 Hz.

Noise is one of the fundamental environmental factors impairing health and well-being. Whereas in the acoustic frequency range the handling of noise is well grounded and regulated, in the infrasound and the ultrasound ranges not only is the understanding of perception lacking but also fundamental requirements for measuring instruments as well as applicable, practice-related measurement instruc...

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Scanning electron microscope images of a JAWS circuit with individual details of the circuit, and a photo of the JAWS chip, contacted on a special chip carrier.

By the triple stacking of Josephson junctions and by the series connection of eight circuits with a total of 63 000 junctions, the output voltage of a pulsedriven AC Josephson voltage standard could be increased to an effective value of 1 V. Such voltage standards allow spectrally pure, arbitrary waveforms to be generated and are, therefore, also referred to as Josephson Arbitrary Waveform...

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Hygrometer for Atmospheric Investigation.

Water vapor measurements rank among the most important – but also the most difficult – measurements aboard research aircraft. During the past five years, PTB has been developing (partly in cooperation with Forschungszentrum Jülich) two completely new hygrometer instrument families (“SEALDH” and “HAI”) which – due to consistent metrological traceability – promise more reliable measurement data.

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Realizing the aim of “Industry 4.0”, also in the process industry, will bring about great technical challenges. Within the scope of PTB’s cooperation with the companies R. Stahl, Siemens and ABB, a project was launched which has clear aims for “Industrial Ethernet”: “Industrial Ethernet” should be easy to use in potentially explosive atmospheres; interoperability between various manufacturers...

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Optical clocks are deemed the clocks of the future. In optical clocks, the atoms, which act as a “pendulum”, are resonantly excited by means of optical radiation. Compared to cesium atomic clocks – on which the SI base unit, the second, is currently based – their excitation frequency is much higher. Therefore, the resonance quality is much better. This implies considerably increased clock accuracy...

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Advisory Board

The portable LIDAR system for measuring three-dimensional wind speed at wind energy locations attracted the interest of many visitors during the laboratory tours.

The Kuratorium of PTB, which is made up of highranking representatives from the fields of economics and science, as well as from verification authorities, fulfills an important function as an advisory committee to PTB and to the Federal Ministry for Economic Affairs and Energy (BMWi). In addition to meetings which take place as needed throughout the year, the annual meeting of the Kuratorium is an...

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Presidential Board

Participants in the Leadership Day Plus

The outcome of the 2014 PTB staff survey was, all in all, very positive. Nevertheless, there was evidence that employee satisfaction could be improved if leadership factors such as communication and cooperation were given greater emphasis during day-to-day activities. The Presidential Board of PTB has responded to the survey’s outcome by introducing appropriate measures.

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PTB‘s Vice-President Dr. Roman Schwartz (third from left), and representatives of other certified organizations after having received the „berufundfamilie” (work and family) certificates

PTB underwent the “work and family audit” (audit “berufundfamilie”) for the first time last year. This ascertained that PTB already had comprehensive basic conditions which are beneficial for staff and that it offered support in combining work and family life before the audit took place. These things include the flexible organization of working time, matching the current stage of an employee’s...

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Quality Management

In 2015, PTB’s technical quality management (QM) system, which is concentrated on its core services in calibration, measurements, testing, and metrological research and development, once again won unconditional recognition at home and abroad. Supplementary to the legal regulations that apply to higher federal authorities, the basis of this recognition was provided by: DIN EN ISO/IEC 17 025; the...

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Since the beginning of 2015, standard DIN EN ISO/ IEC 17 025, “General requirements for the competence of testing and calibration laboratories”, has been undergoing an in-depth revision. A coordinated position concerning this revision was developed within PTB and introduced at the national standardization level in the DIN working committee of “Certification Principles (Principles of Conformity...

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Technology Transfer

Cooperation projects with industrial firms, projects funded by third parties and out-licensing of know-how and patents are the essential elements of industry-related research. In 2015 alone, 40 new direct cooperation projects with industrial firms were established. Creating and exploiting patents represents an important element in the structured transfer of knowhow from PTB to the economy. Of all...

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Legal Metrology

On 1 January 2015, the new Measures and Verification Act came into force. This overall package helped to fundamentally modernize the measures and verification legislation; the existing high level of protection of German metrology, however, will be maintained. Now that legal metrology has been newly regulated in this way, identical requirements are valid for both European and nationally regulated...

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Technical Cooperation

An expert testing a collector of solar-thermal energy within the scope of the Technical Cooperation with Mexico.

The transition to renewable energies and increased energy efficiency is also high on the political agenda in Latin America and the Caribbean. By 2014, an impressive 54 % of the demand for energy was already covered by regenerative sources – mainly by large-scale hydropower plants which are, however, socially and environmentally controversial. Therefore, the potential for renewable energies remains...

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Press and Information Office

Impressionen vom PTB-Stand auf der IdeenExpo 2015

For nine days in July 2015, many of PTB’s staff lived according to the motto: “We are at the IdeenExpo!” For the first time, PTB took part in this large annual fair focusing on sciences and technology which mainly addresses students.

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Screenshot of the top of the new homepage www.ptb.de

Sometimes things start to age. And then they need to be revived. This is why PTB has developed a new Internet site – with a new design, a new structure and lots of new material. Particular attention has been paid to being up-to-date and user-friendliness. On 18 May 2015 the old website was „taken off the web“ and replaced by the new one – which is available at the old address (Opens internal link in current windowwww.ptb.de).

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