PhD fellowship in the field of “Superradiant optical atomic clocks" at the Niels Bohr Institute

University of Copenhagen


PhD fellowship in the field of “Superradiant optical atomic clocks" at the Niels Bohr Institute, University of Copenhagen


Two 3-year PhD fellowships in the field of “Superradiant optical atomic clocks" are available in the Quantum Metrology group at the Niels Bohr Institute, University of Copenhagen, Denmark, with an expected start 1 February 2020 or shortly thereafter.


The fellowships are funded by the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 813114 Innovative Training Network "MoSaiQC”.


About MoSaiQC

The European Innovative Training Network MoSaiQC is training 15 PhD candidates (also called Early Stage Researchers (ESR) in this context) to become experts on optical atomic clocks. The ESRs will work on cutting edge projects developing new types of clocks or clocks with high integration and thereby acquire a wide range of skills from the foundations of ultracold atom quantum measurement devices (quantum mechanics, atomic physics, quantum optics), over engineering (laser systems, vacuum, electronics, software) to applications (search for changes in fundamental constants, gravitational wave detection, geology, network synchronization, navigation,...). After their PhD, the ESRs will be able to make significant contributions in academia, industry and society. The training material developed by MoSaiQC will be publicly available and thereby advance the education of further students.


MoSaiQC consists of ten academia and industry partners of the European Quantum Flagship consortium iqClock and three further partners to provide a unique training experience for the ESRs. The iqClock consortium is developing an integrated optical clock and a new type of optical atomic clock, superradiant clocks. The ESR projects will take place in the laboratories and research centers of iqClock and the ESRs will develop Modular Systems for advanced integrated Quantum Clocks (MoSaiQC), such as advanced atomic sources, lightweight integrated atomics chambers, high-finesse cavities, flexible laser systems, resilient frequency stabilisation systems, modeling tools, and more. These systems go beyond what is currently developed in iqClock but will immediate be used to advance the iqClock project. The ESRs are working within the iqClock teams, giving them hands-on experience not only with the specific systems they develop, but with entire optical clocks. Half-year secondments and visits of ESRs to other partners will broaden the horizon of the ESRs and give them exposure to the application of optical clocks.


About your project
ESR9 - Ultra stable clock laser system for studies of superradiant clock on a kHz wide transition

The early-stage researcher will develop an ultra-stable reference laser and use it to investigate superradiant lasing on the kHz transition in strontium. University of Copenhagen has realized pulsed lasing on the kHz transition in strontium and will use the know-how from this proof-of-concept in order to realize a continuous superradiant laser on the kHz transition within the iqClock project. Highly stable reference lasers are an essential tool in characterizing atomic clocks, and providing high levels of control in cold atom systems for quantum simulations. By characterizing the frequency characteristics of the superradiant laser the ESR will facilitate the accuracy estimations and developments towards compact superradiant clocks. A secondment at DFM (Danish fundamental metrology) will focus on laser stabilization for optical frequency standards. Visits to University of Amsterdam, University Nicolaus Copernicus and ESP Central will contribute essential training in other superradiant laser systems and their application.


ESR10 - Automated superradiant clock on a kHz wide transition

The early-stage researcher will work on the optimization of lasing dynamics in a superradiant optical atomic clock and the subsequent automation of both a mHz transition and kHz transition superradiant lasers. University of Copenhagen (UCPH) has investigated time-dependent dynamics in mK temperature atomic samples, and further investigations of the lasing mechanism in unconfined atoms from a continuous source will be pursued here. The ESR will be part of the direct collaboration between UCPH, and University Nicolaus Copernicus with a secondment at the latter institute. Focus is on experimental infrastructure allowing a robust clock operation and implementation of automated optimization protocols. Visits to University of Amsterdam, DFM (Danish fundamental metrology) and NKT photonics will allow excellent training in cold atomic sources, frequency metrology, commercial laser systems and entrepreneurship.


The positions are available for a 3-year period and your key tasks as a PhD student are:

  • To manage and carry through your research project
  • Attend PhD courses
  • Write scientific articles and your PhD thesis
  • Teach and disseminate your research
  • To conduct secondments at the partner institutes
  • Work for the department

Principal supervisor is professor Jan W. Thomsen, Niels Bohr Institute,

Eligibility criteria

  • The researcher must not have resided or carried out his/her main activity (work, studies, etc.) in the country of his/her host organization (Denmark) for more than 12 months in the 3 years immediately prior to his/her recruitment - unless as part of a procedure for obtaining refugee status under the Geneva Convention.
  • The researcher must be Early Stage Researcher (ESR): at time of recruitment he/she must be in the first 4 years (full-time equivalent research experience) of his/her research careers and must not have been awarded a doctoral degree.


Further requirements

Marie Curie Training Networks offer a unique opportunity to get cutting-edge training in a multidisciplinary environment with a focus on academic and personal development of the PhD fellows. The supervisors in the network each provides specific competences, and as part of the network you develop your skills and carry out research both independently and as part of a network of 15 PhD fellows. The consortium ensures exchange of ideas through network-wide training events, summer schools and intersectoral secondments. As a PhD fellow in the MoSaiQC network, you need to have good social skills, be innovative and goal-oriented and be willing to conduct the planned secondments.


Applicants should hold an MSc degree or equivalent in the field of physics, photonics, electronics or a related discipline. Applicants must have an excellent background in atomic physics or optics-related experiments. Applicants must have an ability to understand and express themselves in both written and spoken English to a level that is sufficiently high for them to derive the full benefit from the network training.


About the host and secondment institute
University of Copenhagen is the largest research and education institution in Denmark. Internationally, the University is highly competitive and is ranked as one of the leading universities globally with the most recent Shanghai rankings placed the University as No. 30 worldwide and No. 6 in Europe. This is also reflected by its membership of the prestigious International Alliance of Research Universities.


The Niels Bohr Institute (NBI) has more than 500 employees and over 40 full professors. It has a broad basis in quantum physics, solid state physics, particle physics, astrophysics, geophysics and biophysics, as well as a strong international environment. UCPH has a strong commitment to its doctoral programme and NBI recruits over 35 new PhDs annually, about half being foreign students, which ensures a multicultural and international environment. NBI participates in large-scale international collaborations such as CERN and the MAX IV/ESS centers and has significant international collaborations. The principal supervisor, Jan W Thomsen, is an expert in experiments on cold group II atoms such as Mg, Sr and Yb as well as the field of ultra-stable frequency references.


Terms of employment
Employment will start 1 February 2020 or shortly thereafter.


The terms of employment and salary are in accordance with Memorandum on Job Structure for Academic Staff. Terms of appointment and payment accord to the agreement between the Ministry of Finance and The Danish Confederation of Professional Associations on Academics in the State, and according to the rules and regulations laid down by the European Union’s Horizon 2020 Marie Skłodowska-Curie Action European Training Network.


The PhD study must be completed in accordance with The Ministerial Order on the PhD programme (2013) and the University’s rules on achieving the degree. Salary, pension and terms of employment are in accordance with the agreement between the Ministry of Finance and The Danish Confederation of Professional Associations on Academics in the State. Depending on seniority, the monthly salary begins around 27.135 DKK /approx. 3.633 EUR (April 2019-level) plus pension.


More information
More information about the MoSaiQC project can be found at


For further information about the position, applicants are encouraged to contact principal supervisor Professor Jan W. Thomsen, the Niels Bohr Institute, or postdoc Stefan Alaric Schäffer, the Niels Bohr institute,


Your application must be submitted electronically by clicking ‘Apply now’ below. The application must include the following documents in PDF format:

  1. Motivated letter of application (max. one page, stating which PhD project you are applying for and detailing your motivation and background for applying for the specific PhD project)
  2. CV incl. education, experience, language skills and other skills relevant for the position
  3. Master of Science diploma and transcript of records. If not completed, a certified/signed copy of a recent transcript of records or a written statement from the institution or supervisor will do
  4. Publication list (if relevant)

The University wishes our staff to reflect the diversity of society and thus welcomes applications from all qualified candidates regardless of personal background.


The deadline for applications is 14 November 2019, 23:59 GMT +2.


We reserve the right not to consider material received after the deadline, and not to consider applications or letters of recommendation that do not live up to the above-mentioned requirements.


The further process
After the expiry of the deadline for applications, the authorized recruitment manager selects applicants for assessment on the advice of the hiring committee. All applicants are then immediately notified whether their application has been passed for assessment by an unbiased assessor.


The assessor makes a non-prioritized assessment of the academic qualifications and experience with respect to the above-mentioned area of research, techniques, skills and other requirements listed in the advertisement.


Once the assessment work has been completed each applicant has the opportunity to comment on the part of the assessment that relates to the applicant him/herself.


You can read about the recruitment process at


The applicant will be assessed according to the Ministerial Order no. 242 of 13 March 2012 on the Appointment of Academic Staff at Universities.


Interviews for the position will be held in the second half of December via Skype, Zoom, or equivalent.

In your application, please refer to