General information
Organisation
The French Alternative Energies and Atomic Energy Commission (CEA) is a key player in research, development and innovation in four main areas :
• defence and security,
• nuclear energy (fission and fusion),
• technological research for industry,
• fundamental research in the physical sciences and life sciences.
Drawing on its widely acknowledged expertise, and thanks to its 16000 technicians, engineers, researchers and staff, the CEA actively participates in collaborative projects with a large number of academic and industrial partners.
The CEA is established in ten centers spread throughout France
Reference
SL-DAM-26-0617
Direction
DAM
Thesis topic details
Category
Condensed Matter Physics, chemistry, nanosciences
Thesis topics
Behavior of matter under isothermal dynamic compression: displacement of chemical reactivity; synthesis of new metastable materials; phase transition mechanisms.
Contract
Thèse
Job description
The Diamond Anvil Cell equipped with piezoelectric actuators, or d-CED, is an innovative device that can generate dynamic compressions and decompressions over a wide range of pressure variation rates. The d-CED thus enables finely controlled dynamic stresses to be applied, with (de)compression rates that can vary over several orders of magnitude along isothermal paths. This paves the way for the creation of reference databases for the validation of microscopic mechanisms. Furthermore, the compression or decompression rates can be equated to ultra-fast heating or cooling rates of the sample, offering the possibility of exploring, in a highly controlled manner, certain phenomena still debated in the literature, such as the maximum stability of a solid beyond its melting point.
The objective of this thesis is to exploit the new possibilities offered by d-CED to demonstrate new phenomena or gain a detailed understanding of certain effects discussed in the literature, by performing ultra-fast temperature variations. A first application will consist of studying the nucleation kinetics of rare gases (Ar, Ne, Kr) as a function of the compression rate, and comparing them with recent measurements made at the XFEL in cryogenic jets. A second objective will be to study chemical changes, with an initial study focusing on the modification of the reactivity of nitromethane, a reference explosive. Another area of study will concern the synthesis of new molecular compounds from mixtures of dense molecular fluids (N2, H2, O2).
University / doctoral school
Physique en Île-de-France (EDPIF)
Paris Sciences et Lettres
Thesis topic location
Site
DAM Île-de-France
Requester
Position start date
01/10/2026
Person to be contacted by the applicant
Pépin Charles
charles.pepin@cea.fr
CEA
DAM/DPEM//DPEM
CEA, DAM, DIF, F-91297 Arpajon Cedex, France
0169264000
Tutor / Responsible thesis director
LOUBEYRE Paul
paul.loubeyre@cea.fr
CEA
DAM/DPEM//DPEM
CEA/DAM Ile-de-France
Bruyères-le-Châtel
F-91297 Arpajon Cedex
0169264000
En savoir plus
https://www-lmce.cea.fr/team/condensed_matter_physics/loubeyre.html
https://www-lmce.cea.fr/about.html