PhD position in Molecular Spectroscopy - Precision measurements of trapped H2+

Research / Academic

We are looking for a motivated and interested PhD-student, with a degree in physics or physical chemistry and with experience in atomic/molecular/optical physics and/or molecular spectroscopy, who wishes to work with us in the international and stimulating environment of the joint Quantum Metrology group at LaserLaB Amsterdam.

This project aims to measure the level structure of weakly-bound molecular states of H2+ with unprecedented accuracy using novel quantum technologies. These transitions in the microwave and THz range are particularly sensitive to the proton-to-electron mass ratio (mp/me) and exotic spin-dependent interactions. For this, you will be involved in developing a novel ion trap for quantum-logic spectroscopy using H2+ (spectroscopy) and Be+ (logic) ions. You will develop a continuous-wave laser system at 313nm (using fiber lasers, periodically poled crystals, and optical cavities for second-harmonic generation) to laser cool Be+ ions, which are then used for sympathetic cooling of the molecular ions. The molecular ions are selectively prepared by field-ionizing the optically excited molecular Rydberg states of H2 (we use extreme-UV, UV and visible laser light). To guide the experimental developments and understand the measured spectra, you will dive into the details of the molecular Hamiltonian, advanced angular momentum theory, optical Bloch equations, laser cooling simulations, and many other topics.

During the PhD, you will engage with various aspects of molecular spectroscopy and experimental physics, including ultrahigh vacuum, CAD design, optics and lasers, electronics, and scientific programming. There is also the possibility of delving into the theory of molecular Rydberg states, photoionization, and photodissociation using multichannel quantum-defect theory.


  • Bachelor/Master in physics or physical chemistry
  • Affinity for spectroscopy and molecular physics.
  • Most important is that you are bright, enthusiastic, work well in a team, are eager to learn, and of course that you are enthusiastic about this intriguing project!

As a university, we strive for equal opportunities for all, recognizing that diversity takes many forms. We believe that diversity in all its complexity is invaluable for the quality of our teaching, research, and service. We are always looking for talent with diverse backgrounds and experiences. This also means that we are committed to creating an inclusive community so that we can use diversity as an asset.

We realize that each individual brings a unique set of skills, expertise, and mindset. Therefore we are happy to invite anyone who recognises themselves in the profile to apply, even if you do not meet all the requirements.

Salary Benefits:

A challenging position in a socially engaged organisation. At VU Amsterdam, you contribute to education, research and service for a better world. And that is valuable. So in return for your efforts, we offer you:

  • a salary of minimum € 2.770,00 (PhD) and maximum € 3.539,00 (PhD) gross per month, on a full-time basis. This is based on UFO profile PhD candidate. The exact salary depends on your education and experience.
  • a full-time position (1.0 FTE). Your employment contract will initially last 1 year. If there is sufficient perspective, this will be extended to a total of 4 years.

We also offer you attractive fringe benefits and regulations. Some examples:

  • A full-time 38-hour working week comes with a holiday leave entitlement of 232 hours per year. If you choose to work 40 hours, you have 96 extra holiday leave hours on an annual basis. For part-timers, this is calculated pro rata.
  • 8% holiday allowance and 8.3% end-of-year bonus
  • contribution to commuting expenses
  • optional model for designing a personalized benefits package
  • a wide range of sports facilities which staff may use at a modest charge

De Boelelaan 1085