PhD positions

Open Positions
In the Quantum Logic Spectroscopy research group, we work on precision spectroscopy of trapped and laser-cooled atomic ions. To this end, we develop quantum computer-inspired techniques for the coherent manipulation of ions and their spectroscopy for applications such as high-precision optical atomic clocks.
Your tasks will include:
- Enhancing the Ca+-based multi-ion experiment to attain uncertainty values so far unequalled
- Implementing and evaluating multi-ion manipulation, detection and cooling techniques
- Developing and implementing quantum algorithms for ion entanglement to improve the statistical uncertainty
- Enhancing dynamic decoupling algorithms to suppress environmental effects
- Developing methods for correlated clock retrieval in close collaboration with the Al+ quantum logic clock
- Presenting the scientific results at international conferences
- Participating in international projects such as the TSCAC EU project and the DQ-mat Collaborative Research Center (CRC)
We offer:
- A position at one of the world’s leading research institutions which has an excellent infrastructure
- Excellent national and international connections
- Intensive PhD supervision in an interdisciplinary team as well as practical training in modern experimental technologies of laser and quantum physics and frequency metrology
- Research leave abroad via our wide-ranging network
- Remuneration in accordance with the collective bargaining agreement for the public service (Tarifvertrag öffentlicher Dienst Bund – TVöD for the federal level)
- For PhD students, remuneration is based on salery group E13, (85%)
- Good transport connections (bus and bike); free parking
- In-house daycare center and canteen
Your profile:
- You have completed your university studies in physics (master’s degree/German Diplom) with a very good degree.
- You are interested in developing and performing high-precision experiments.
- You have a high level of commitment, an ability to work independently, and a willingness to learn.
- You are a strong team player with excellent communication skills.
- You have a very good command of spoken and written English.
- Having a good knowledge of atomic physics, quantum optics, laser cooling, laser spectroscopy, or related fields is an advantage.
- You are willing to travel within Germany and abroad within the scope of your assignment.
- You must have the physical ability to work in a laboratory and perform experiments at external sites.
If you are interested, please contact Prof. Dr. Piet O. Schmidt or Dr. Lennart Pelzer
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.
Background
Coulomb crystals are an interesting system for scaling trapped-ion precision spectroscopy to multiple particles. They are the basis for a new generation of ion optical clocks with improved stability and thus higher time resolution in fundamental physics tests and applications such as relativistic geodesy. At the same time, the highly controlled environment in state-of-the-art ion traps allows for 10-19-level systematic uncertainties in such many-body spectroscopic references [Keller et al., PRA 99, 013405 (2019)].
Description of work
We use linear 115In+/172Yb+ ion chains for precision spectroscopy. Yb+ is used in searches for physics beyond the Standard Model and tests of the Einstein Equivalence Principle [Dreissen et al., Nat. Commun. 13, 7314 (2022)]. Our In+/Yb+ optical clock has demonstrated operation with multiple clock ions and participated in local and international frequency comparisons with an evaluated systematic uncertainty in the low 10-18 range [t.b.p.].
By cooling crystals close to their motional ground state, time dilation in clock ions can be explored with a relative precision of 1 x 10-19. Such a clock is ideally suited to explore and test physics at the intersection of quantum mechanics and general relativity. In addition, we are investigating novel quantum-enhanced interrogation protocols for multi-ion clocks pushing the bounds of today’s best atomic clocks with an atomically resolved and highly controlled quantum system.
Skills and Requirements
We are looking for an ambitious and highly motivated experimentalist with very good analytic thinking. Experience in one or more of the following fields is advantageous: spectroscopy of trapped ions or atoms, lasers and laser stabilization, time & frequency metrology, opto-electronic controls and systems. We expect the candidate to have finished their university degree in physics or a comparable field with a very good degree. They should have good command of spoken and written English, excellent communication skills and the integrate well into an international team.
Position
The position is initially limited to three years; an extension of the contract is possible. The salary will be paid in accordance with remuneration group 13 TVöD Bund (85%). Applicants should send their CV and application to Prof. Dr. Tanja Mehlstäubler (tanja.mehlstaeubler@ptb.de).
Contact
Prof. Dr. Tanja E. Mehlstäubler
QUEST Institute at PTB
Bundesallee 100
38116 Braunschweig, Germany
Tel.: +49 531 592-4710
E-Mail: tanja.mehlstaeubler@ptb.de
https://www.quantummetrology.de/quaccs
Doctoral candidates in the field of quantum logic spectroscopy of highly charged ions (85% E13 TVöD)
Highly charged ions (HCIs) are ubiquitous in the observable universe and have many advantageous properties for fundamental physics tests and use as next-generation optical clocks. Building on our recent breakthrough in the clock-like laser spectroscopy of highly charged ions with a precision jump of nine orders of magnitude, the following tasks will be pursued:
- Participating in the ERC project titled ‘FunClocks’ and in other international cooperation projects
- Setting up an electron beam ion trap (EBIT) with an integrated optical resonator to investigate Doppler-free spectroscopy of HCIs in close cooperation with the Max Planck Institute for Nuclear Physics (MPIK), Heidelberg
- Participating in developing quantum logic search techniques to enable the rapid identification of narrow optical transitions in HCIs
- Performing optical frequency measurements at the technological limit
- Developing optical clocks based on HCIs with an uncertainty of 10‑18
- Presenting the scientific results at international conferences
Your profile:
- You have completed your university studies (master’s degree or German Diplom) in physics or a comparable field with a very good degree.
- You are interested in developing and performing high-precision experiments.
- You are highly committed and capable of working autonomously.
- You are a strong team player with excellent communication skills.
- You have a very good command of spoken and written English.
- A good knowledge of atomic physics, quantum optics, laser cooling, laser spectroscopy, or related fields would be an advantage.
- You are willing to travel within Germany and abroad within the scope of your assignment.
- You must have the physical ability to work in a laboratory and perform experiments at external sites.
We offer:
- A position at one of the world’s leading research institutions which has an excellent infrastructure
- Excellent national and international connections
- Intensive PhD supervision in an interdisciplinary team as well as practical training in modern experimental technologies of laser and quantum physics and frequency metrology
- Research leave abroad via our wide-ranging network
- Remuneration in accordance with the collective bargaining agreement for the public service (Tarifvertrag öffentlicher Dienst Bund – TVöD for the federal level)
- Good transport connections (bus and bike); free parking
- In-house daycare center and canteen
The post is initially limited to three years; an extension of the contract is possible. You will be employed at our Braunschweig site.
Apply here
For more information, please contact Prof. Dr. Piet O. Schmidt
In the research group "Quantum Logic Spectroscopy" we deal with precision spectroscopy of trapped and laser-cooled atomic ions. Therefore, we develop quantum computer-inspired techniques for the coherent manipulation of ions and their spectroscopy for applications such as high-precision optical atomic clocks.
Your tasks:
Development of compact optical setups with automated optimisation of operating parameters
Integration of the resulting hardware in a transportable Al+ quantum logic clock
Participation in the automation of the clock for continuous operation and characterisation of the clock
Participation in in-field measurement campaigns outside the laboratory environment for relativistic geodesy
The post is initially limited to three years; an extension of the contract is possible. You will be employed at our
Hannover site in the brand-new HITec lab building. The remuneration will be paid in accordance with remuneration group 13 TVöD Bund (85 %).
We offer:
- An excellent research environment (DQ-mat CRC 1227, Excellence Cluster 2123) with access to PTB's unique infrastructure
- Practical training in modern experimental techniques in laser and quantum physics and active participation in the development of experiments at the forefront of quantum physics research.
- Possibility to present scientific results at international conferences
- We encourage research stays abroad with our international collaborators
Your profile:
- You have obtained an excellent university degree in physics
- You are interested in developing and realising precision experiments
- You are highly committed and capable of working both autonomously and together as part of a team, and you are willing to improve your skills
- You are a team player and have good communication skills
- Sound knowledge of atomic physics and experience in the field of quantum optics, laser cooling, laser
spectroscopy or related subjects is advantageous - You have the physical ability to work in a laboratory and to perform experiments outside the institute
If you are interested, please contact Prof. Dr. Piet O. Schmidt