Postdoc modélisation thermodynamique d’un système oxyde pour applications laser

Site IRCER, Institut de Recherche sur les Céramiques

This position is related to the HEMERALD project, financially supported by the French National Research Agency (ANR).

Context of the HEMERALD project:
The HEMERALD (High Efficiency of Massive Emitting ceRAmic for the 1.7-2.7 μm LASER winDow) project proposes to develop new transparent ceramics as active gain materials for the 1.7-2.7 μm LASER window. It gathers the skills of 3 academic partners (ICMCB-Bordeaux, CEMHTI-Orléans and IRCer-Limoges).

Objectives:
To take into account the needs in terms of thermomechanical properties, resistance to corrosion threshold in atmosphere due to humidity and toxicity of the elements and stability under irradiation, the consortium proposes to explore through a fast ceramic approach, the (Gd1-xHox)2O3-Ga2O3-Nb2O5 phase diagrams to identify new Ho3+-doped transparent ceramics.

Considering Ho as a doping agent, the overall thermodynamic system will be restricted to Ga-Gd-Nb-O. From this quaternary system one should reduce it to the focused pseudo-ternary Ga2O3-Gd2O3-Nb2O5. The first part of this thermodynamic study is to gather all available data and to start building the Ga-Gd-Nb-O database, leading to the identification of lacking data. These identified lacking data (ternary compounds, solid solutions, solidus and liquidus) will be experimentally evaluated using calorimetry, HT-XRD, and diffusion couples. If experiments are not conclusive, a theoretical approach using DFT methods should help for thermodynamic data acquisition.

The thermodynamic data, for all phases involved in calculations, will be modeled in order to obtain their Gibbs Energy as a function of the temperature, and in case of solutions, as a function of the composition, using the CALPHAD method. The objectives of this thermodynamic work is to gather and to acquire all thermodynamic data in order to model the overall Ga-Gd-Nb-O system using the CALPHAD method, or at least parts of interest if data are not totally available even theoretically.

Requirements:
A PhD in Materials Science or related. Strong skills in thermodynamic modeling and more especially with the CALPHAD Method. Strong knowledge in experimental determination of thermodynamic data (DTA, DSC, Calorimetry) as well as in materials characterization (XRD, SEM/EDS). Knowledge in DFT would be appreciated but not mandatory.

Duration: 12 months.

Gross annual Salary: 36.9 k€

Application:
To apply, please submit the application documents to Dr. Olivier RAPAUD (olivier.rapaud@unilim.fr) with an email entitled “HEMERALD Postdoctoral Application” with your full name.
The application documents must include a complete CV, transcripts of all degrees, a list of reference contacts, and a cover letter (no more than 2 pages) summarizing your previous works. Review of applicants will begin immediately and will continue until the position is filled. Fail to provide requested documents may cause delay in the review process.
Applicants are encouraged to visit the research lab and the University of Limoges through the website before application: https://www.ircer.fr/ and https://www.unilim.fr/. Due to the pandemic context with difficulties for relocation, the starting date will be negotiable, especially for international applicants.
For more information about IRCER: EN | FR

Pour postuler, envoyez votre CV et votre lettre de motivation par e-mail à olivier.rapaud@unilim.fr