Doctorate in computational high pressure physics (M/F)
PhD @French National Centre for Scientific Research posted 21 hours agoJob Description
General information
Job title: PhD in high pressure computational physics (M/F)
Reference: UMR7605-ALERON-015
Number of positions: 1
Work location: PALAISEAU
Publication date: Friday, June 6, 2025
Contract type: Fixed-term contract Doctoral student
Contract duration: 36 months
Thesis start date: September 1, 2025
Workload: Full
Remuneration: €2,200.00 gross monthly
Section(s) CN: 04 – Physics of atoms, molecules and plasmas. Optics and lasers
Description of the thesis subject
This PhD project focuses on first-principles simulations of hydrogen-helium (H/He) mixtures and their extensions to more complex planetary fluids under extreme pressure-temperature (PT) conditions, such as those found inside Jupiter, Saturn, and Uranus. The main objective is to provide fundamental insights into H/He demixing, electronic transport properties, and trace element behavior, using a combination of density functional theory molecular dynamics (DFT-MD) and machine learning potentials (MLP).
The research will begin by investigating the behavior of hydrogen and helium in these extreme environments, particularly how they can phase separate under different thermodynamic conditions. These processes are thought to play a key role in shaping the internal structure, magnetic fields, and long-term evolution of gas giants. The student will use powerful simulation tools to model this behavior, including recent machine learning techniques that expand the scope and speed of calculations.
In a second phase, the focus will be on studying how trace elements such as neon move through these mixtures. This part of the project will shed light on why certain elements appear to be absent from the outer layers of planets like Jupiter, a long-standing question in planetary science.
Finally, the project will be expanded to include water in the mixtures, allowing the student to simulate more realistic planetary materials. These simulations will predict how the presence of water alters key properties such as electrical conductivity and reflectivity, both important for understanding observations from space missions and telescopes.
Throughout their doctoral studies, the student will gain experience with cutting-edge computational tools and contribute to a better understanding of the physical processes that govern giant planets. The results will support ongoing efforts to build more accurate models of planetary interiors and interpret data from current and future planetary exploration missions.
The main activities of the recruited person will be:
-Set up and perform DFT-MD simulations in an HPC environment.
-Implement new tools for analyzing simulation data.
-Analyze, organize and visualize data. Close collaboration with fellow experimentalists and modelers of planetary interiors.
– Summarize and present results in group meetings and conferences.
-Prepare results for publication and put them in context with literature data.
The candidate should have a background in high pressure physics/chemistry, plasma physics, materials science, or engineering. Prior knowledge of density functional theory and/or basics of molecular dynamics is crucial for the project. We will particularly appreciate candidates with experience in performing DFT-MD simulations with VASP or Abinit or MD simulations with LAMMPS in an HPC environment. Additional knowledge of machine learning potentials, free energy calculations, or structure prediction is a plus. The candidate should have experience in programming and data analysis (python, C/C++, …). Strong communication skills are highly appreciated. The person to be recruited must be able to work in a team as well as independently. The candidate must be able to write documents and report. A good command of English is a plus.
Interested candidates should send a cover letter and a detailed CV including the email addresses of two people who can provide letters of reference.
Work context
The French National Center for Scientific Research (CNRS) is a major player in fundamental research on a global scale. The CNRS is divided into 17 delegations, including the one in Ile-de-France Gif-sur-Yvette. Attached to this delegation, the Laboratory for the Use of Intense Lasers (LULI) is located on the École Polytechnique campus, but is also present on the Orme des Merisiers site and at Jussieu.
LULI is a research infrastructure that provides experimental facilities (LULI2000 and APOLLON) located on two different sites. The laboratory has approximately 110 employees (researchers, technicians, administrative staff, doctoral students).
Within LULI, the recruited person will be part of the PHYDHEL team. The thesis will involve close collaboration with our collaborators at the University of Rostock (Germany) and the CEA (France). The project will involve experimental campaigns at the LULI2000 facilities, which have already been accepted and will be scheduled during the first year of the doctoral thesis. The project is associated with a GENCI computing time allocation at the TGCC and CINES HPC centers, which will be renewed annually. In addition, a local cluster for test calculations is available.
The position is located in a sector covered by the Protection of Scientific and Technical Potential (PPST), and therefore, in accordance with regulations, requires that your arrival be authorized by the competent authority.
Constraints and risks
Missions are expected (France, Europe and outside the EU). Travel between the different LULI sites is also possible.
