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We show that the simultaneous coupling of two laser scanning non-linear microscopies (2-photon excited fluorescence and third harmonic generation microscopy) give functional and morphological information for improving our understanding on intracellular calcium flows.
We show that the electronic part of the nonlinear susceptibility chi(3) of thin films can be easily measured by third harmonic microscopy. The phenomenon of third harmonic generation (THG) is excited by a femtosecond laser beam focused at the interface between the thin film and a reference layer. The value of chi(3) is deduced from the THG intensity(More)
We describe the promising development of third-harmonic generation (THG) in laser scanning microscopy for study of the functional imaging of live biological cells. The dynamics of Ca(2+) in biological cells is shown. The Ca(2+) signal consists of a transient increase in the intracellular concentration. THG microscopy allows one to temporally visualize the(More)
The gravitational wave detector Virgo is presently being commissioned. A significant part of last year was spent in setting up the cavity length control system. This work was carried out with steps of increasing complexity: locking a simple FabryPerot cavity, then a Michelson interferometer with Fabry-Perot cavities in both arms, and finally recycling the(More)
Peculiar light-matter interactions can break the rule that a single beam polarization can address only two states in an optical memory device. Multistate storage of a single beam polarization is achieved using self-induced surface diffraction gratings in a photoactive polymer material. The grating orientation follows the incident light beam's polarization(More)
Although coherent light is usually required for the self-organization of regular spatial patterns from optical beams, we show that peculiar light-matter interaction can break this evidence. In the traditional method of recording laser-induced periodic surface structures, a light intensity distribution is produced at the surface of a polymer film by an(More)
Nonlocal communication between two laser light beams is experimented in a photochromic polymer thin films. Information exchange between the beams is mediated by the self-induction of a surface relief pattern. The exchanged information is related to the pitch and orientation of the grating. Both are determined by the incident beam. The process can be applied(More)
The interaction of cells with nanoscale topography has proven to be an important modality in controlling cell responses. Topographic parameters on material surfaces play a role in cell growth. We have synthesized a new bio compatible polymer containing photoswitching molecules. Stripepatterned (groove/ridge pattern) were patterned and erased with ease on(More)
We present the results of a laser beam passing through a turbulent medium. First we measure the geometric parameters and the spatial coherence of the beam as a function of wind velocities. A multifractal detrended fluctuation analysis algorithm is applied to determine the multifractal scaling behavior of the intensity patterns. The measurements are fitted(More)
  • Samia Chalal, Nabila Haddadine, +4 authors A. Haroun
  • 2014
Composites consisting of carbopol (CP) and ceramic titanium dioxide nanoparticles, TiO2 have been investigated. The CP-TiO2, organic-inorganic hybrid composites have been prepared in DMF by heating the mixture with a constant rate of 1 ̊C/min, up to 30 ̊C, 45 ̊C, 60 ̊C, 80 ̊C, 100 ̊C and 120 ̊C. Proprieties such as absorption, structure and external aspect(More)