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PhD subjects

3 sujets IRAMIS

Dernière mise à jour : 15-12-2019


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• Soft matter and complex fluids

 

SL-DRF-20-0434

Research field : Soft matter and complex fluids
Location :

Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l’Energie

Laboratoire Interdisciplinaire sur l’Organisation Nanométrique et Supramoléculaire

Saclay

Contact :

Florent Malloggi

Fabienne TESTARD

Starting date :

Contact :

Florent Malloggi
CEA - DSM/IRAMIS/NIMBE/LIONS

+3316908 6328

Thesis supervisor :

Fabienne TESTARD
CEA - DRF/IRAMIS/NIMBE/LIONS

01 69 08 96 42

Personal web page : http://iramis.cea.fr/Phocea/Membres/Annuaire/index.php?uid=jrenault

Laboratory link : http://iramis.cea.fr/nimbe/lions/

Self-assembled metamaterials made by block copolymers

SL-DRF-20-0544

Research field : Soft matter and complex fluids
Location :

Service Nanosciences et Innovation pour les Materiaux, la Biomédecine et l’Energie

Laboratoire Interdisciplinaire sur l’Organisation Nanométrique et Supramoléculaire

Saclay

Contact :

Patrick GUENOUN

Starting date : 01-10-2018

Contact :

Patrick GUENOUN
CEA - DRF/IRAMIS/NIMBE/LIONS

01-69-08-74-33

Thesis supervisor :

Patrick GUENOUN
CEA - DRF/IRAMIS/NIMBE/LIONS

01-69-08-74-33

Personal web page : http://iramis.cea.fr/Pisp/patrick.guenoun/index.html

Laboratory link : http://iramis.cea.fr/nimbe/lions/

Metamaterials are "artificial" materials which are created to reach properties inaccessible to natural homogeneous materials. Optical properties like negative refractive indices could be achieved by an adequate structuring of materials at a scale lower than the wavelength of the light. In this PhD work, we shall obtain such a structuration by combining the self-assembly of copolymers on surfaces and the insertion of gold nanoparticles in the copolymer matrix. The copolymer matrix of copolymers provides the nanostructuration and the desired geometry thanks to microphase separation on top of the substrate whereas the gold nanoparticles presence confers the expected optical properties. This PhD thesis project in collaboration between LIONS at CEA Saclay (U. P. Saclay) and the Paul Pascal Research Center (CRPP) in Bordeaux will benefit from both environments to lead an experimental study which will consist in preparing surfaces where cylindrical or bicontinuous phases of copolymers will be directed perpendicularly to the substrate. After synthesis in the laboratory and insertion of gold nanoparticles in the structures, the optical properties of the obtained material will be measured and analyzed for modeling.

Taking up the challenge of the glass transition by optical manipulations of molecules.

SL-DRF-20-0287

Research field : Soft matter and complex fluids
Location :

Service de Physique de l’Etat Condensé

Systèmes Physiques Hors-équilibre, hYdrodynamique, éNergie et compleXes

Saclay

Contact :

David CARRIÈRE

François LADIEU

Starting date : 01-10-2020

Contact :

David CARRIÈRE
CEA - DRF/IRAMIS/NIMBE/LIONS

0169085489

Thesis supervisor :

François LADIEU
CEA - DRF/IRAMIS

01 69 08 72 49

Personal web page : http://iramis.cea.fr/Pisp/francois.ladieu/

Laboratory link : http://iramis.cea.fr/Phocea/Vie_des_labos/Ast/ast_groupe.php?id_groupe=214

More : http://iramis.cea.fr/Pisp/david.carriere/

According to the Nobel Prize awardee P.W. Anderson “The deepest and most interesting unsolved problem in solid state theory is probably the nature of glass and the glass transition”. This sentence reflects the fact that we still do not know if glasses are a true thermodynamic phase of matter or, on the contrary, if they are just out of equilibrium liquids which have become too viscous to flow on human time scales. Finding the answer to this seemingly simple question is hampered by the fact that, when decreasing temperature, the relaxation time of glass forming liquids becomes so large that one cannot rely onto the experimental techniques used to evidence standard thermodynamic phase transitions (e.g. liquid/gas transition or liquid/crystal transition). By using a totally new approach we aim at unveiling the nature of the glass transition, which is of great importance both for fundamental physics and for applications, since glasses play an increasing role in modern technologies (e.g. in optical fibers for communications, in photovoltaic devices, or in airplanes fuselages).

More precisely, we have just built an experiment corresponding to the “ideal thought experiment” proposed recently by some theorists, so as to unveil the presence or the absence of a true thermodynamic glass transition. In this experiment a fraction of molecules, randomly chosen in space, is pinned and one monitors the response of the rest of the liquid: if this pinning of a small fraction of molecules changes the global dynamics of the liquid, this means unambiguously that an order was present before establishing the pinning field, even though the extremely complex nature of this order had made it impossible to evidence by standard experimental tools. The approach that we have built involves: i) designing the optically sensitive molecules; ii) building an optical setup allowing the realize pinning in the well-chosen liquid; iii) comparing the experimental results to the theoretical predictions. The internship and/or the thesis consists in working onto the improvment and the exploitation of this experiment.

This project is a collaboration gathering all the required expertise between physicists, chemists, and theoreticians working at CEA Saclay –near Paris- and in the University of Montpellier. The internship and/or the thesis will mainly take place in the NIMBE/LIONS and SPEC/SPHYNX laboratories in the CEA center of Saclay. We are looking for a candidate who, by relying onto the expertise available in the laboratories, really wants to invest herself/himself onto this project by providing us his/her skills in experimental physics (mainly optics, and dielectric spectroscopy).

 

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