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Accueil du site > Jobs - PostDoc - These > Annonce stage M2 / PIIM, Marseille / Yves Ferro

Annonce stage M2 / PIIM, Marseille / Yves Ferro

par Nord & Ile de France - 28 janvier

Hydrogen at the W/Cu interface

USPP pseudo-potentials and PAW atomic data

DFT calculations and Statistic Thermodynamics

Hydrogen diffusivity at the Cu/W interface will be investigated in the framework of a five months internship. This work will be carried out at the LPIIM (Laboratoire de Physique des Interactions Ioniques et Moléculaires) in the PATP team (Physique Atomique et Transport dans les Plasma).

In a first step, the pseudo potentials that model the ionic-cores of tungsten and copper will be built. Pseudo-potentials allow to consider a small number of valence electron in the DFT calculation. The computing time and used memory is consequently diminished enabling to consider systems and models of larger size. We already have a 14 electrons pseudo-potential for tungsten. However, a new pseudo-potential with lower valence electron will have to be built while fulfilling the requirement of keeping the same transferability to various chemical environment.

The pseudo-potential for tungsten and copper will be ultra-soft (USPP) type, while atomic data for Projected Augmented Waves will also be considered. Calculations will be done with the Quantum Espresso code that solves the Kohn-Sham in a plane-waves basis-set for periodic systems.

In the continuation of this work in the frame of a PhD, the energetics of the hydrogen interaction with copper, tungsten and the W/Cu interface will be investigated. On the basis of these DFT results, a statistic model will be established to determine the atomic fraction of hydrogen, in W, Cu, at the interface, the experimental conditions of temperature and pressure leading to the formation of defects, the pressure of hydrogen in case of void formation at the interface, etc.

While of fundamental interest, this work is tightly linked to the plasma-wall interaction in nuclear fusion reactors such as the experimental thermonuclear reactor ITER. This works is funded by Euratom and benefits from a large collaborative network in Europe and outside Europe. In particular, we have an experimental long-standing collaboration with Robert Kolasinski SANDIA national Lab, Livermore, USA.

The interested student will ideally have a strong background in electronic structure calculations (plane waves DFT would be appreciated), statistic thermodynamics, skills in Python / Fortran 90 coding, and knowledge of Linux/Unix.

Contact : yves.ferro@univ-amu.fr ;