Onderwijs of Opleiding vacatures in Ter Aar

PhD position - Laser cooling and trapping Helium molecules

• W&N Gebouw

• 0.8 / 1

• MSc

• Publicatiedatum

  26-11-2025

• Amsterdam

• Faculty of Science

• Sluit op

  28-02-2026

PhD position - Laser cooling and trapping Helium molecules

• W&N Gebouw

• Amsterdam

• 0.8 / 1

• Faculty of Science

• MSc

• Sluit op

  28-02-2026

• Publicatiedatum

  26-11-2025

This PhD project is about the first direct laser cooling and trapping of a homonuclear diatomic molecule - He_2. Precision measurements of Rydberg states will allow QED tests and provide the polarizability of He atoms for a quantum pressure standard.

Your function

We are looking for a motivated and interested Ph-studentD, with a degree in physics or chemistry and with experience in laser physics, spectroscopy, and/or optical technology, 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 create the first ultracold gas of a directly laser-cooled homonuclear molecule, the helium dimer He_2. Starting from a supersonic beam, novel laser slowing and cooling techniques will be employed to create a trapped dense gas of ultracold molecules. Choosing the He_2 molecule constitutes a paradigm change in the field of ultracold molecules, as it will constitute the lightest and simplest molecule ever laser-cooled. This provides a controllable, simple 4-electron system at record low temperature, allowing quantum sensing and precision measurements to test QED and to study the quantum nature of collisions with unprecedented accuracy - while being accessible to highly accurate ab initio computational methods.

During the PhD, you will engage with various aspects of experimental physics, including ultrahigh vacuum, CAD design, optics and lasers, electronics, and scientific programming. There is also the possibility to delve into the theory of molecular Rydberg states and collisions using scattering theory.

Your profile

• Bachelor and Master in physics or chemistry
• Affinity for atomic, molecular, or optical 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.

What do we offer?

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 € 3.059,00 (PhD) and maximum € 3.881,00 (PhD) gross per month in the fourth year, on a full-time basis. This is based on UFO profile PhD candidate.
• 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

About us

QMLA group in the Department of Physics and Astronomy

The Quantum Metrology and Laser Applications group at LaserLaB, Vrije Universiteit Amsterdam, is a very international group, consisting of some 20 strongly collaborating senior and junior scientists. The group focuses on precision measurements of atomic and molecular systems, using advanced laser techniques as well as techniques to cool the motion of atoms and molecules. For this, they use the joint infrastructure at LaserLaB, with a variety of lasers ranging from ultrastable to ultrafast, connected to atomic clocks and frequency comb lasers. The goals are to test fundamental theories of physics (like Quantum Electrodynamics), to determine fundamental constants (like the proton-electron mass ratio), and to search for physics beyond the Standard Model, such as fifth forces and extra dimensions.

Faculty of Science

Researchers and students at VU Amsterdam's Faculty of Science tackle fundamental and complex scientific problems to help pave the way for a sustainable and healthy future. From forest fires to big data, from obesity to malnutrition, and from molecules to the moon: we cover the full spectrum of the natural sciences. Our teaching and research have a strong experimentally technical, computational and interdisciplinary nature.

We work on new solutions guided by value-driven, interdisciplinary methodologies. We are committed to research, valorisation and training socially engaged citizens of the world who will make valuable contributions to a sustainable, healthy future.

Are you interested in joining the Faculty of Science? You will join undergraduate students, PhD candidates and researchers at the biggest sciences faculty in the Netherlands. You will combine a professional focus with a broad view of the world. We are proud of our collegial working climate, characterised by committed staff, a pragmatic attitude and engagement in the larger whole. The faculty is home to over 11,000 students enrolled in 40 study programmes. It employs over 1,600 professionals spread across 10 academic departments.

Vrije Universiteit Amsterdam

We are located on one physical campus, in the heart of Amsterdam's Zuidas business district, with excellent location and accessibility. Over 5,500 staff work at the VU and over 30,000 students attend academic education.

Diversity

Diversity is the driving force of the VU. The 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.

Interested

Are you interested in this position and do you believe that your experience will contribute to the further development of the project? In that case, we encourage you to submit your application.

Please provide a detailed CV, your diploma, a cover letter, and the names and contact details of two potential references.

Applications will be considered until the position is filled.

Diversity is the driving force of the VU. The VU wants to be accessible and receptive to diversity in disciplines, cultures, ideas, nationalities, beliefs, preferences and worldviews.

Therefore, we are always searching for people whose backgrounds and experience contribute to the diversity of the VU community.

Neem contact op met

dr.

Are you interested in this position and do you believe that your experience will contribute to the further development of the project? In that case, we encourage you to submit your application.

Please provide a detailed CV, your diploma, a cover letter, and the names and contact details of two potential references.

Applications will be considered until the position is filled.