The most accurate optical single-ion clock worldwide

12-Feb-2016 - Atomic clock experts from the Physikalisch-Technische Bundesanstalt (PTB) are the first research group in the world to have built an optical single-ion clock which attains an accuracy which had only been predicted theoretically so far. As early as 1981, Hans Dehmelt, who was to be awarded a Nobel ...

A deep look into a single molecule

10-Feb-2016 - A German research group has demonstrated the first implementation of a non-destructive state detection technique for molecular ions. Piet Schmidt and his colleagues from the QUEST-Institute at the Physikalisch-Technische Bundesanstalt (PTB) observed changes in the rotational state of a trapped ...

Ultrastable materials investigated in depth

Measuring Thermal expansion at low temperatures for future space missions

25-Nov-2015 - Space holds numerous fascinating objects which we can only investigate by observing their radiation - even beyond the visible range. For space telescopes such as the European Space Agency's (ESA) infrared observatory Herschel, whose mission is to observe radiation in the far-infrared, cooling the ...

The fundamental constants are still constant

Atomic clocks prove the stability of the mass ratio of protons to electrons

20-Nov-2014 - Are the fundamental constants really constant? Recent investigations carried out at the Physikalisch-Technische Bundesanstalt (PTB) have shown that one essential fundamental constant - namely the mass ratio of protons to electrons - can have changed only by a maximum of one part in a million over ...

A big step towards the redefinition of the kelvin

PTB scientists determine a new value of the Boltzmann constant

28-Sep-2011 - Metrologists are measurement artists who are very precise – in the case of the Boltzmann constant up to the sixth decimal place. Whoever is able to determine it very exactly will cause a small revolution in the field of worldwide temperature measurement: The temperature unit will then no longer ...

Accurate measurement of radioactive thoron possible at last

PTB develops first primary standard worldwide for calibration of thoron measuring instruments

09-Mar-2011 - "Many people are now saying: 'Is it really that easy? Then why didn't anyone think of it a long time ago?' But you have to have the right idea at the right time," says Annette Röttger, physicist at the Physikalisch-Technische Bundesanstalt (PTB), in a pleased way. Annette Röttger and her ...

The "new" kilogram is approaching

Avogadro constant determined with enriched silicon-28

11-Feb-2011 - A milestone in the international Avogadro project coordinated by the Physikalisch-Technische Bundesanstalt (PTB) has been reached: With the aid of a single crystal of highly enriched 28Si, the Avogadro constant has now been measured as exactly as never before with a relative overall uncertainty ...

The "profile" of neon becomes more exact

PTB researchers determine the polarizability of neon with extreme accuracy - their procedure helps to revise theoretical models and is also of use for other elements

29-Jul-2010 - Small or large, quiet or communicative - the fundamental characteristics of a person form his/her behaviour. In principle, it is the same with chemical elements. And the better the "profile" of an element is known, the better its behaviour can be understood and controlled in practical ...

Graphene: What projections and humps can be good for

Investigators from Hanover and Braunschweig measure how the electronic properties of graphene can be controlled with purposefully used roughnesses

21-Apr-2010 - At present, graphene probably is the most investigated new material system worldwide. Due to its astonishing mechanical, chemical and electronic properties, it promises manifold future applications – for example in microelectronics. The electrons in graphene are particularly movable and could, ...

Uniform analyses for clean drinking water in Europe

PTB scientists receive award for concept of comparability and traceability of water analyses

14-Dec-2009 - Clean water is a matter of survival for humans, particularly when it is used for drinking, cooking and for food manufacture. Therefore, the EU member countries have in several guidelines undertaken to guarantee their citizens sustainable clean drinking water. The requirement for this is, however, ...