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Laboratory experiments are increasingly composed of electronic hardware and computer controlled. In most cases the quality of the equipment (mechanical, electronics) is very good but the software is inadequate and not very flexible to the needs of researchers. LIONS chose to use the open source control system  TANGO developed by a collaboration of European synchrotrons ans scientific institutes (ESRF, SOLEIL...).
The nanotechnologies require to build complex heterostructures at an atomic scale. Those are generally carried out by deposition on a substrate (metal or oxide). The control of the physical phenomena of the growth and the realization of dots or thin films of well defined structure is one of the keys of the realization of new devices with new properties. The teams of the DRECAM largely use the various techniques of deposition, control of the growth and analyses and contribute to develop them.
X-rays are used to investigate the structural properties of solids, liquids or gels. Photons interact with electrons, and provide information about the fluctuations of electronic densities in heterogeneous matter. A typical experimental set-up is shown on Figure : a monochromatic beam of incident wave vector is selected and falls on the sample. The scattered intensity is collected as a function of the so-called scattering angle 2 teta.
The specificity of the group is the use of high-performing time-resolved spectroscopy. DNA and its constituents are fragile systems so particular care is taken with regards to excitation energy and sample handling. Time-resolved fluorescence (fluorescence decays, fluorescence anisotropy decays and time-resolved fluorescence spectra) can be recorded from 100 fs to 100 ns using a combination of two detection techniques; fluorescence upconversion and time-correlated single photon counting.
Permanents impliqués : Mickaël Bouhier, Jean-Charles Méaudre. La Reflectance Transformation Imaging (RTI), ou imagerie de transformation par réflectivité, est une méthode d’imagerie basée sur la compilation de clichés dont la seule variable est l’orientation de la source lumineuse. Cette technique, dite 2.
Si les surfaces possèdent intrinsèquement des propriétés intéressantes (propriétés optiques ou magnétiques, interface électronique, catalyse, fonction biologique, ...), des fonctions spécifiques peuvent être ajoutées par nanostructuration, ou en déposant un revêtement, ou encore par l'adsorption ou le greffage de molécules aux propriétés spécifiques.
Pour les besoins de leurs recherches, les équipes de l'IRAMIS développent une instrumentation originale.
The femtosecond laser facilities of the DRECAM offer to the national and european researchers, ultra short pulse duration and high intensity laser lines instrumented by numerous diagnostics. These laser beams allow studies on high intensity laser matter interactions as well as two colours experiments. This laser platform provides power peaks until 10TW, intensities of 1019W/cm2 and pulse durations about 35fs.
The magnetic properties of bulk samples and thin films can be studied by Vibrating Sample Magnetometry (VSM) or Magneto-optic Kerr effect (MOKE). Two VSM measuring devices are available in the IRAMIS: - One device in SPEC - One device in SPCSI   For research on low TC superconductors or more generally on electronic and magnetic matter properties at very low temperature,  specific equipments are developped, like a dilution-fridge equipped SQUID magnetometer.
Mass spectrometry is an instrumental technique of analysis resting on the separation, identification and quantification of the components of a sample according to their mass. Thus atoms, molecules or aggragates are extracted in the form of ions, then sorted by a dispersive system: sector of electric or magnetic field, quadripolar filter or time of flight.
  The microfluidics is the science and technology of systems that process or manipulate small amounts of fluids (nanoliter to attoliter), using channels with dimensions of tens to hundreds of micrometers. Since a decade microfluidics is become a powerful tool for fundamental and applied researches. Microfluidics influence subject areas from chemical synthesis and biological analysis to optics and information technology.
Near field microscopies cover a whole of techniques making it possible to visualize the surface of materials at a nanometric scale. These microscopies gather: - Scanning Tunneling Microscopy (STM) - Atomic Force Microscopy (AFM) - Magnetic Force Microscopy (MFM) All these techniques have in common the positioning nanometric of a tip on top of the sample whose position is controlled according to the selected signal (current, force).
Les neutrons permettent de sonder la matière et leur sensibilité aux éléments légers et au magnétisme en font une sonde unique et originale. A l'IRAMIS , l’utilisation de la spectrométrie neutronique dans divers domaines de la recherche fondamentale et appliquée est développée au Laboratoire mixte CEA-CNRS Léon Brillouin à Saclay.
The Raman microspectrometry is an analytical device of primary importance to characterize the crystalline structure of materials. It is a complementary technique to micro X-ray diffraction. This technique is well suited to characterize and determine the distribution of the phases formed in the corrosion layers of iron or steels during very long periods in various environments. Iron oxides, oxy-hydroxides and carbonates are the main phases encountered in these systems.
The researches of the DRECAM are based both on physical and chemical experimentation and on significant theoretical developments. These developments and the comparison with the experiment allow the understanding of the phenomena and the model validation and support lot of research works.
A phenomenon of transport is due to a force whose origin can be varied (electric or magnetic field, gradient of concentration, pressure etc...). Under the heading "transport measurements" are gathered various associated measurement techniques which can be flux measurements (heat, particles, electrical current, etc...), or statistical methods.
x-rays, electromagnetic radiation beyond the remote ultraviolet ray, cover a range wavelength around the tenth of nanometer. This distance is about the distance between atoms in the condensed matter. The diffraction of x-rays thus makes it possible to probe the matter, and to obtain information on the structure, the order and the composition of materials.

 

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