Help make the first measurement of how a proton and a hydrogen atom bind into a molecule. With extreme-UV lasers and ion traps, you will study the most fundamental atomic collisions and find out how the first antimatter molecules could be made.
Deadline 28 Feb ’27 · Published 2026-10-23
- Research fields: Physics
- Job types: PhD
- Education level: University graduate
- Weekly hours: 30.4—38 hours per week
- Salary indication: €3204—€4051 per month
- Location: De Boelelaan 1085, 1081 HV, Amsterdam
Job description
When a proton meets a hydrogen atom, the pair can emit a photon and stay together as H₂⁺. This is how the first molecules formed after the Big Bang, and it is one of the proposed routes to the first antimatter molecule, yet it has never been measured. In the NWO Vidi project SAMURAI, you will study these collisions one quantum state at a time: instead of colliding atoms, we use lasers to prepare a hydrogen molecule at the moment of a collision and watch it fall apart. You will be part of a small group in which experiment and theory go hand in hand.
Your duties
- excite H₂ with two tunable extreme-ultraviolet lasers (60–205 nm), built in our lab and unique in the Netherlands, and image the fragments with velocity-map imaging
- aim for the first spectroscopic observation of the excited electronic states of H₂⁺, calculated by Edward Teller in his PhD thesis in 1930 and never seen since
- trap H₂⁺ ions and use millimetre waves and magnetic fields to control how they come apart
- work towards the first measurement of radiative association: joining a cold proton and a cold hydrogen atom with light, next to a crystal of laser-cooled Be⁺ ions
- compare your data with multichannel quantum-defect theory and scattering calculations, and contribute to the theory yourself if you like
- develop your skills in lasers and nonlinear optics, ultrahigh vacuum, electronics, CAD design and scientific programming
- present your results at international conferences and publish them in peer-reviewed journals
Requirements
- an MSc degree (or close to completing one) in physics, physical chemistry or a related field
- affinity with quantum mechanics and atomic, molecular and optical physics, and an interest in lasers and electronics
- good command of spoken and written English
- most important: you are curious, enjoy building things that work, like working in a team, and want to spend four years on a question nobody has answered yet
As a university, we strive for equal opportunities for all, recognising 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 realise 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.
Conditions of employment
Fixed-term contract: 1 year.
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 € 3.204,00 (PhD) and maximum € 4.051,00 (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 position for at least 0.8 FTE. Your employment contract will initially last 1 year. Afterwards, the possibility of expansion exists.
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
- group insured for partial disability with employer contribution of 50% of the premium
- optional model for designing a personalized benefits package
Employer
Vrije Universiteit Amsterdam
Quantum Metrology and Laser Applications (QMLA), LaserLaB Amsterdam
The Quantum Metrology and Laser Applications group in the Department of Physics and Astronomy is a very international group of some 20 strongly collaborating senior and junior scientists. The group carries out precision measurements on atoms and molecules, using advanced laser techniques and methods to cool their motion. It shares the infrastructure of LaserLaB Amsterdam, with lasers ranging from ultrastable to ultrafast, connected to atomic clocks and frequency combs. The aims are to test fundamental theories such as quantum electrodynamics, to determine fundamental constants such as the proton-to-electron mass ratio, and to search for physics beyond the Standard Model.
Molecular Ions group
Within QMLA, the Molecular Ions group led by Dr. Max Beyer studies the simplest molecules there are, with one, two, three and four electrons: H₂⁺, H₂, He₂⁺ and He₂. These systems are simple enough to be calculated with extreme precision, so every measurement is a direct test of theory, and we do both: experiments and ab initio, quantum-defect and scattering calculations. In the lab we laser-cool molecules, trap ions and use light from across the electromagnetic spectrum, from the extreme ultraviolet through the visible and infrared to millimetre waves. More at www.molecularions.com.
Faculty of Science
Working at the Faculty of Science means collaborating with students, lecturers and researchers who are focused on their field, yet have a broad view of the world. We are proud of a positive and inclusive workplace culture within the faculty, where we work together with great energy and a pragmatic attitude to tackle social challenges. At the Faculty of Science, scientists and students work on fundamental and complex societal issues for a sustainable, healthy and just future.
From forest fires to big data, from obesity to malnutrition, from helium to the universe and from genetics to medicine: our education and research cover the full breadth of science, from molecules to mankind. Our academic education and research are highly experimental, technical and interdisciplinary in nature. That is why we collaborate extensively with leading scientific institutes and industry. The faculty has more than 8,000 students studying in one of the 39 programms and employs more than 1,400 staff across 10 scientific departments, making us one of the largest science faculties in the Netherlands.
Vrije Universiteit Amsterdam
Vrije Universiteit Amsterdam stands for values-driven education and research. We are open-minded experts with the ability to think freely - a broader mind. Maintaining an entrepreneurial perspective and concentrating on diversity, significance and humanity, we work on sustainable solutions with social impact. By joining forces, across the boundaries of disciplines, we work towards a better world for people and planet. Together we create a safe and respectful working and study climate, and an inspiring environment for education and research. Learn more about our codes of conduct.
We are located on one physical campus, in the heart of Amsterdam's Zuidas business district, with excellent location and accessibility. Over 6,150 staff work at the VU and over 31,000 students attend academic education.
Diversity
Diversity is the driving force of VU Amsterdam. VU wants to be accessible and receptive to diversity in disciplines, cultures, ideas, nationalities, beliefs, preferences and worldviews. We believe that trust, respect, interest and differences lead to new insights and innovation, to sharpness and clarity, to excellence and a broader understanding.
We stand for an inclusive community and believe that diversity and internationalisation contribute to the quality of education, research and our services. Therefore, we are always searching for people whose backgrounds and experience contribute to the diversity of the VU community.
Additional information
Do you want to be the one who makes this measurement? Then we look forward to your application. Please include:
- a detailed CV
- a cover letter describing your background, motivation and skills (max. 1 page)
- transcripts with all your grades from your BSc and MSc studies
- your MSc thesis, or a draft if it is not finished yet
- your diploma(s)
- the names and contact details of two references
Applications will be considered until the position is filled. For questions, contact m.beyer@vu.nl.
More about the project: SAMURAI and www.molecularions.com