GDR Micro Nano Fluidique

Mois : février 2013

We look for a candidates for a postdoctoral position in Paris, at ESPCI, within our team (EC2M – Collective Effects in Soft Matter, to study experimentally

To be eligible, this application should be the first postdoctoral position of the candidate.
To obtain the position, the candidate will have to apply for the second round of a grant for which we successfully went through the first round. The rate of success for the second round is 25%. In case of success, the position is to be taken before june 2014 (and reasonably after summer 2013).
The file must be sent before the 7th of March at midnight!

Necessary documents include a CV. A letter of recommendation is also welcome.

Tout dossier reçu incomplet sera considéré comme inéligible et seuls les projets soumis avant la date limite via le site de soumission en ligne seront étudiés.

Titre du projet de recherche : Trafic passif et actif de gouttes sur réseaux

Sujet développé (à présenter en 1 page maximum en français ou en anglais, en précisant notamment le contexte, les objectifs, les méthodes et les résultats attendus)

Hundreds of natural and industrial processes ultimately rely on the transport of mobile agents in obstacle,or channel,networks. Prominent examples concern: particle filtration, blood flows in micro-vessels, droplet-based-microfluidics. In all these examples, passive particles are advected by external force fields and traffic through heterogeneous environment. A second important class of traffic phenomena deals with self-propelled agents. The most obvious realizations are the traffic flows of vehicle, and pedestrian in the urban networks but numerous similar processes take place in living systems at much smaller scales: bacteria in polluted soils and in host, or contaminated, organs; or the so-called cytoplasmic streaming, which ensures the transport of organelles through the eukaryotic cells along the cytoskeletal network.

The diversity of the systems, where traffic flows is involved calls for investigating their universal properties, thereby making the problem highly appealing from a fundamental perspective. In return, a generic comprehension of the mechanisms at play would drive the emergence of potential applications in many different fields of technological importance.

We intend to develop a generic understanding of the traffic dynamics in obstacle and channel networks. More precisely we shall concentrate on one well-identified axis ofresearch: Clogging. When the particle size compares to the typical width of the channels, or to the distance between obstacles, the traffic flows in fluidic network becomes a highly challenging problem. The particles then behave as “mobile clogs”, which locally modify the network conductivity. The local particle current then depends a » priori on the position of all the other particles in the network, making the problem nonlinear and nonlocal. We aim at providing the first quantitative experimental investigation of this problem in extended networks for both driven passive and active droplets.

To achieve these goals, we will take advantage of the expertise we have recently developed on the creation, the manipulation and the observation of a new kind of self-propelled agents, namely Swimming droplets. The postdoc will benefit from this expertise and, depending on the profile of the best candidate we will identify, he will contribute to the experimental work on one or both experiments and/or work on the modelisation of the above situations.

At the end of the day, we expect (i) to develop a unique analogic toolbox to investigate the collective dynamics of active and passive agents in heterogeneous media and (ii) a precise description of the traffic statistics both in ordered and disordered 2D networks.

Research Topic: Rare earth elements are strategic materials that can be found nowadays in most consumer products, but which production processes produce very large amounts of harmful emissions. Hence 97% of its production currently occurs in China. The project REE-CYCLE (for Rare Earth Element reCYCling with Low harmful Emissions) will aim at developing more environmentally friendly processes, and could therefore have a huge societal, economic and environmental impact at a global level.

Such processes are based on liquid-liquid extraction. Liquid-liquid extraction, also known as solvent extraction and partitioning, is a method to separate compounds based on their relative solubilities in two different immiscible liquids, usually water and an organic solvent. It is an extraction of a substance from one liquid phase into another liquid phase. In order to develop a new process, one need to study new Liquid–liquid extraction components, associated phase diagrams and both from an experimental and theoritycal point of view. If performed in a traditional manner this can be a very lengthy process that can take up to few years per phase diagram. In REE-CYCLE we propose to address this search using microfluidic devices that should enable phase diagram studies in a matter of days or weeks.

This first ERC REE-CYCLE position aims at developing the core device on which the project will greatly depend: an integrated microfluidic chip that can perform liquid-liquid extraction of lanthanides in a very reproducible and controlled environment. The microfluidic chip and sensors will be embedded in a dedicated sealed package. The manipulation of fluids inside the channels will be enabled by pressure-driven flow controllers, in conjunction with high resolution flow sensors. All this architecture will be driven with a dedicated software interface, to control the laminar flows through the microfluidic chip and perform real-time measurements.

In this context, the objectives for this post-doctoral position are to:

  • Review existing vapor-phase sensors, and selection of appropriate technology relevant to the project targets, based upon validation tests that should be carried out in the first post-doc period.
  • On parallel, design of both the microfluidic liquid-liquid extraction chip, and its packaging.
  • Follow-up of the chip fabrication process (carried out in the 8inches wafer fab clean-rooms at CEA-LETI).
  • Improve/adapt the existing test bench overall setup and software interface.
  • Fluidic tests: by varying the flow rates in both channels, to control the exchanging time.

Context and collaboration: This work located in Grenoble, France, in the middle of the French Alps will benefit from a very multidisciplinary and international environment at the interface of three institutes:

This work will benefit from the prestigious framework of the ERC ( and namely the advanced project « REE-CYCLE » (PI, T. Zemb & co –PI JC Gabriel: The objective of this job is key to the project and it will therefore place the candidate in a very special and core position.

The successful candidate will have access to many different pieces of knowledge, technologies, experiments as well as characterization tools, ranging from simple tabletop optical microscope to the latest generation synchrotron (ESRF, : for phase diagram studies). This position is therefore a great opportunity to enhance your knowledge base, your skills as well as your value on the job market.

Key Qualifications:

  • Successful candidates should have at minima an Engineering degree with few years of practical experience in a relevant field (microfluidics, micro- nanotechnology, applied physics, instrumentation, chemistry, etc) and a publication track record.
  • Candidate should have an interest and/or experience in microfluidics, different sensing methods, instrumentation development, as well as complementary simulation and design. Valuable. Hands-on experience with vapor –phase sensing methods, labview programming, microfabrication techniques is a plus.
  • Candidate should be available to interview at CEA/Grenoble and to start work ASAP.
  • Demonstrated ability to work on interdisciplinary projects and to quickly and efficiently acquire new technical skills outside the sphere of primary training.
  • A target-oriented, structured attitude and team spirit are absolutely necessary. Excellent communication skills and fluency in English are required (working language will be either French or English). We further expect creativity in problem solving and integrative skills.
  • Energetic, proactive, results-oriented, and self-motivated team player with strong organizational skills.
  • Ideal candidate will be adept at planning, prioritizing, multi-tasking, organizing, following through, and thinking on his/her feet.

We offer: This position comes with a very attractive benefit package, typical of French working environment. It will provide excellent working conditions in a highly interdisciplinary environment.

Starting date: The position is vacant and will start as soon as possible (duration up to 24 Months).

Position host location: CEA, MINATEC Campus, 17 rue des Martyrs, 38054 Grenoble Cedex 9, France

Application: Candidate should send as soon as possible CV, Cover Letter and References to:

Immediate superior: Dr. Jean-Christophe P. Gabriel

Scientific and advisory board:

Name Technical part covered in the project Institution
V. Agache microfluidics design, fabrication and instrumentation CEA/LETI
J-C. Gabriel Microfabrication, vapor-phase sensors, sensing methods/tests. CEA
T. Zemb Phase diagrams, liquid-liquid extraction ICSM
R. Laucournet Recycling process LITEN