Postdoc in absorption spectroscopy simulation at CEA (France)

A Post-doctoral position is opened at Université Paris Saclay / CEA (France)

Calculation of X-Ray Absorption spectra for Warm Dense Matter with ABINIT

The study of Warm Dense Matter (WDM) is a challenging field that is at the crossroads between condensed matter and plasma physics. XANES (X-ray Absorption Near Edge Structure) is a standard technique in condensed matter physics measurements which brings valuable information on electronic and ionic structure. This technique was recently extended to WDM regime. A precise description of X-ray absorption spectrum is a key diagnostic to follow the complex mechanism of phase transition both theoretically and experimentally. XANES absorption are computed using Density Functional Theory within the framework of Projected Augmented-Wave and linear response theory. This description makes use of frozen core approximation which severely limit the description for extreme pressure condition (~100GPa and above). The challenge is now to go beyond the frozen core approximation keeping in mind that an all electrons calculation is numerically out of reach for this extreme condition. One promising possibility is to make possible the relaxation of the core orbitals consistently with the valence electrons.

The candidate will implement new solutions to improve the description of XANES spectra for extreme conditions in ABINIT sofware. He/She will run DFT based simulations on massively parallel computers to obtain X-ray absorption spectra for metals in extreme pressure (T>10000K) and temperature (P>100GPa). The CEA is a leading national center for numerical simulations and has also access to multiple computational resources in several HPC centers. The candidate will have close interaction with experimental teams all along the project.

The candidates should have a PhD in Materials Science, Physics or Chemistry, be familiar with density functional theory, have excellent coding skills (e.g. Fortran and MPI), demonstrated by significant development of some software applications. The candidates should not have passed the PhD by more than 3 years at the beginning of their contract.

The work location is CEA/DAM Ile de France, near Arpajon (South Paris)

Applicants should send their CV (pdf) including their publication list as well as a brief motivation letter to vanina.recoules@cea.fr and marc.torrent@cea.fr.

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