The ILL is an international research facility at the forefront of neutron science and technology. Its High-Flux Nuclear Reactor delivers the world’s most intense neutron beams to a suite of over 40 scientific instruments. Every year, some 1800 international researchers visit the ILL to carry out cutting-edge experiments across a range of scientific disciplines, driving innovation in the fields of health, energy, the environment and quantum materials. The ILL is also involved in the production of radioisotopes for medical applications. The ILL employs over 500 staff from 25 different countries, in a diversity of careers and a multicultural and inclusive environment.

The Science Division at ILL brings together close to 200 scientists, engineers, and technicians who work collaboratively to provide users with advanced experimental capabilities and expert scientific support. The DS is responsible by operating world-class neutron scattering instruments, supporting an international user community, conducting cutting-edge research, and developing new experimental techniques. In addition, the division drives the development of next-generation instrumentation and computational tools, fosters international collaborations, and contributes to advanced training.

Context

The objectives of the ILL Theory group are both to provide theoretical support to ILL scientists and users and to develop its own projects on neutron-related subjects. In this respect it favours long-term scientific collaborations and tries to cover a wide range of scientific domains.

Our scientific activity thus covers subjects ranging from strong correlation in condensed matter to the simulation of cell membranes in biophysics. We also use a variety of techniques, from analytical methods to Monte-Carlo simulation and ab-initio electronic structure calculations. As our aim is to be an effective support to ILL instrument scientists and ILL users, most of our work is directly related to experimental projects. To be efficient in providing theoretical support, however, requires that we also spend some time developing new methods.

Your tasks

The goal of the mission is to work on ab-initio electronic structure and spectroscopic calculations in strongly correlated quantum materials with a special focus on magnetic and multiferroic systems. 
•    The successful candidate will work on specific compounds, in close collaboration with experimentalists. 
•    The candidate will use ab-initio methods to develop effective models able to bring a coherent understanding of the experimentally observed properties of specific compounds. A special focus will be given to the understanding of neutron diffraction data, such as magnetic structure, magnetic excitations, etc. 
•    The candidate will potentially participate in the building of databases on magnetic systems for further machine learning.

Further information can be obtained by contacting the Head of the Theory group: Marie-Bernadette LEPETIT - email: lepetit@ext.ill.fr (please do not send your application to this address).

The successful candidate should have:
•    A PhD in condensed matter physics or quantum chemistry obtained less than 4 years ago.
•    A strong background in quantum mechanics, a reasonable knowledge of electronic structure calculations (such as DFT, wave-function methods, etc.).
•    Experience with Linux.
•    Some knowledge of group theory or crystallography would be an asset.
•    Some knowledge in artificial intelligence would be appreciated.

The deadline for applications is 4 October 2026.