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doctoral candidate specializing in physics (19-105-4)Wednesday, 25. September 2019

The Physikalisch-Technische Bundesanstalt (PTB) is the National Metrology Institute of the Federal Republic of Germany with scientific and technical service tasks. It furthers progress and reliability in metrology for society, the economy and science.


In Department 4.4, Time and Frequency, of Division 4, we are looking for a


doctoral candidate specializing in physics


to join us as soon as possible.

This position is available on the basis of a 3-year fixed-term contract. You will be employed at our Braunschweig site.

The remuneration will be paid in accordance with remuneration group 13 TVöD Bund (85 %).


Your tasks:

Our working group deals with research & development for optical clocks with trapped ions. Thanks to a number of its properties, the Yb+ ion is particularly well-suited for realizing an optical clock exhibiting excellent accuracy. One of this ion's particularities is the electrical octupole transition it provides, which, due to its extremely small natural linewidth, is particularly interesting as a reference for an optical clock. Within the scope of this project, we offer the possibility to do experimental research in an absolutely fascinating area at the internationally renowned time laboratory of PTB.

One of the main goals of our work consists in realizing continuous sympathetic cooling of Yb+ by means of laser-cooled Sr+. In this way, it should be possible to derive maximum benefit from the naturally small linewidth of the octupole transition. Furthermore, combined trapping of Yb+ and Sr+ allows the sensitivity of the Yb+ octupole transition's frequency to be characterized accurately by means of an IR laser, compared to that of thermal radiation. The accuracy of the optical clock setup will then have to be demonstrated by comparing it with existing systems. Due to the electronic structure of the excited state, the Yb+ clock is particularly well-suited for investigating various questions from the field of fundamental physics. Comparison with other optical clocks of PTB can be used, for instance, to search for dark matter or a possible time dependence of the fine-structure constant.

Your tasks in more detail:

  • Realizing the experimental setup for combined trapping of Yb+ and Sr+ ions for sympathetic cooling, including automated experiment control
  • Performing precision measurements of systematic frequency shifts
  • Comparing frequencies with those of other optical clocks of PTB
  • Elaborating scientific publications and presenting the results at international conferences


Your profile:

  • You have completed university studies in physics (German Diplom or Master's).
  • Knowledge of and experience in the following fields would be an advantage: nuclear physics, laser spectroscopy, laser stabilization, analog and digital electronics, automated data acquisition, programming.
  • You are able to perform target-oriented scientific work.
  • You have a good command of spoken and written English.
  • You have excellent communication skills and are a team player.
  • You are willing to travel within the scope of your assignment.


For further information with regard to this position, please contact:

Dr. N. Huntemann, phone: +49 531 592-4430, e-mail: nils.huntemann(at)ptb.de or
Dr. E. Peik, phone: +49 531 592-4400, e-mail: ekkehard.peik(at)ptb.de.


Click here to learn more about our department


PTB promotes the professional equality of women and men and is thus especially interested in applications from women.

Within the scope of the official feasibilities, PTB offers flexible part-time work schemes in order to support in particular the compatibility of work and family life.

Disabled persons will be given priority if they have the same occupational aptitude.


Are you interested? Then we are looking forward to hearing from you.
Please use our

or send us your application to the following postal address:


Physikalisch-Technische Bundesanstalt
Referat "Personal"
Reference number 19-105-4
Bundesallee 100
38116 Braunschweig


Unfortunately, we cannot accept applications sent via e-mail.

The closing date for applications is 25 September 2019.