Abstract: Disclosed is a method for cutting dielectric or semiconducting material with a laser. The method includes the following steps: emission of a laser beam including at least one burst of N femtoseconds laser pulses; spatial separation of the laser beam into a first split beam having a first energy, and respectively, a second split beam having a second energy; spatial concentration of energy of the first split beam in a first zone of the material, respectively, of the second split beam in a second zone of the material, the first zone and the second zone being separate and staggered by a distance dx; and adjustment of the distance between the first zone and the second zone in such a way as to initiate a straight micro-fracture oriented between the first zone and the second zone.

Abstract: The present disclosure relates to a method for arranging atoms in a target array of optical traps with predefined positions comprising: generating a given number of target traps at said predefined positions; generating reservoir traps, said reservoir traps and said target traps forming a traps array; defining allowed paths between traps of the traps array; loading atoms in the traps array to generate an initial loaded traps array; determining the positions of the atoms in the initial loaded traps array; calculating a sequence of moves using a rearrangement algorithm based on said initial loaded traps array and said allowed paths; and applying the sequence of moves to rearrange the atoms in the traps array and form a final loaded traps array.

Abstract: The invention relates to a cellular microcompartment comprising successively, organized around a lumen, at least one layer of pluripotent cells, an extracellular matrix layer and an outer hydrogel layer. The invention also relates to processes for preparing such cellular microcompartments.

Abstract: Disclosed is a device for interaction between a laser beam and a hyperfine energy transition of a chemical species. The device further includes an electro-optic modulator with a single sideband with an input optical waveguide suitable for receiving a source laser beam and an output optical waveguide suitable for generating an output laser beam and an electronic system suitable for generating and applying, simultaneously, a first modulated electrical signal, sin(?1t)) to a first hyperfrequency pulse on a first high-frequency electrode of the electro-optic modulator and, respectively, another modulated electrical signal, cos(?1t)) to the first pulse on another high-frequency electrode of the electro-optic modulator, in such a way as to frequency-switch the output laser beam to a first optical frequency offset from the first pulse with respect to the initial optical frequency.

Abstract: Disclosed is a hybrid inertial measurement system including a cold atom interferometric inertial sensor having a laser source generating a sequence of laser pulses towards a cold atom burst and a conventional inertial sensor attached to the inertial reference frame of the interferometric inertial sensor. The hybrid system includes a signal processing system suitable for receiving an inertial measurement signal from the conventional inertial sensor and for generating in real time a non-linear frequency modulation signal, the feedback loop electronic system being configured to modulate in real time the central optical frequency of the laser according to the modulation signal, such that the cold atom interferometric inertial sensor generates a first hybrid inertial measurement signal by atomic interferometry corrected for the relative movements of the inertial reference frame.

Abstract: A method for generating ultrashort pulses includes directing a master beam having ultrashort pulses and at least one slave beam through an optical gate material. The intensity of the slave beam upstream of the optical gate material is lower than that of the master beam upstream of the optical gate material. The optical gate material and the pulses of the master beam are chosen to induce a Kerr effect when the master beam passes through the optical gate material, the Kerr effect producing a modulation of the phase of the slave beam in association with pulses of the master beam when the slave beam passes through the optical gate material. The modulation of the phase of the slave beam is transformed into a modulation of the amplitude thereof using a complementary optical device to generate a slave beam downstream of the optical gate material having ultrashort pulses.

Abstract: Disclosed is an acoustic resonance spectrometry system for analysing a sample, which includes an optical pump-probe device adapted to generate a pump beam and a probe beam, the pump beam being consisted of a series of ultra-short pump light pulses having a repetition frequency in the spectral domain of the gigahertz, the pump beam being directed towards an optoacoustic transducer to generate a periodic grating of coherent acoustic phonons in the sample, the probe beam being directed towards the sample to form a scattering beam of the probe beam on the grating of phonons, a frequency variation device being adapted to vary the repetition frequency of the pump beam in a spectral range and a photo-detection system configured to measure a scattering signal as a function of the repetition frequency in the spectral range.

Abstract: An optical tomography apparatus comprises: a polychromatic light source, a one-dimensional optical sensor, an interferometric microscope, a one-dimensional confocal spatial filtering system, an actuation system making it possible to perform a one-way scan depthwise of an object to be observed and a processor for reconstructing a two-dimensional image of a section of the object from a plurality of one-dimensional interferential images acquired by the image sensor during the one-way scan. An optical tomography method based on use of such an apparatus is also provided.

Abstract: Coherent spectroscopic methods are described, to measure the total phase difference during an extended interrogation interval between the signal delivered by a local oscillator (10) and that given by a quantum system (QS).

Abstract: Coherent spectroscopic methods are described, to measure the total phase difference during an extended interrogation interval between the signal delivered by a local oscillator (10) and that given by a quantum system (QS).

Abstract: A frequency converter system includes a source that emits a beam having a wide spectral band; and a frequency conversion cell including 1) a birefringent nonlinear crystal having a first phase-matching wavelength, with an input face that receives the beam, an output face that emits at least one frequency-converted beam, and at least two parallel faces different from the input and output faces; 2) means for applying an external mechanical force to at least one of said two parallel faces, resulting in a variation in the birefringence of the nonlinear crystal, the value of the applied external mechanical force being determined so as to obtain phase matching at a second phase-matching wavelength different from the first phase-matching wavelength; and 3) means for adjusting the external mechanical force for wavelength tunability in the frequency conversion cell.

Abstract: A source of directional radiation in an IR band comprises at least a substrate and an external layer comprising controllable cells made of a metal insulator transition material that changes phase depending on its temperature relative to a temperature at which the corresponding wavelength is located in the IR band and that possesses a crystalline phase and an amorphous phase, and control means for controlling the phase change of the cells so as to form in this external layer a diffraction grating when the cells are controlled to the amorphous phase, in order thus to obtain a switchable directional source.

Abstract: According to one aspect, the invention relates to a frequency conversion cell (10) comprising: a birefringent nonlinear crystal (12) characterized by a first phase-matching wavelength, having an input face (121A) for receiving at least one incident beam, an output face (121B) for emitting at least one frequency-converted beam, and at least two parallel faces (120A, 120B) different from the input and output faces; means (14, 14A) for applying an external mechanical force to at least one of said parallel faces (120A), called a force application face, resulting in a variation in the birefringence of the nonlinear crystal, the value of the applied external mechanical force being determined so as to obtain phase matching in the nonlinear crystal at a second phase-matching wavelength different from the first phase-matching wavelength.

Abstract: Techniques for identifying images of a scene including illuminating the scene with a beam of 3 or more wavelengths, polarized according to a determined direction; simultaneously acquiring for each wavelength an image X//(?i) polarized according to said direction and an image X?(?i) polarized according to a direction perpendicular to said direction, X?(?i) being spatially distinct from X//(?i); calculating for each wavelength an intensity image which is a linear combination of X//(?i) and X?(?i), providing an intensity spectrum for each pixel; calculating for each wavelength a polarization contrast image on the basis of an intensity ratio calculated as a function of X//(?i) and of X?(?i), providing a polarization contrast spectrum for each pixel; and calculating a spectro-polarimetric contrast image of the scene, each pixel of this spectro-polarimetric contrast image calculated based on the intensity spectrum and the contrast spectrum of the pixel considered.

Abstract: An ultra-short high-power light pulse source including a first laser pump source (1), a mode-locked laser oscillator (2), a second laser pump source (4), a waveguide (6) capable of inserting spectral phases into the light pulses, and a compressor (8) capable of generating predetermined spectral phases into the light pulses. The waveguide (6) includes an element capable of compensating the predetermined spectral phases generated at least by the compressor (8), the second laser pump source (4) being capable of delivering a second pump light flow (5) having a power PL such that the spectral phases generated by the wave guide (6) are opposed or quasi opposed to the predetermined spectral phases generated by the compressor (8) in order to generate compressed ultra-short light pulses (9) at the output of the compressor (8) with a planar or quasi planar spectral phase.

Abstract: A guided coherent atom source (1) includes elements for generating neutral atoms in a gaseous state (2), elements for cooling the atoms gas (3), elements for generating a magnetic field (4), including an electro-magnetic micro-chip (6) deposited on a surface (18) of a substrate (14), and capable of condensing the atoms in a magnetic trap, elements for generating an electro-magnetic RF field capable of extracting the condensed atoms, optical elements (10) for emitting and directing an optical coherent beam (12) toward the condensed atoms able to guide the condensed atoms, characterized in that the optical elements (10) and the electro-magnetic micro-chip (6) are integrated onto the same substrate (14). An atomic interferometer using such a source is also disclosed.

Abstract: Techniques for identifying images of a scene including illuminating the scene with a beam of 3 or more wavelengths, polarized according to a determined direction; simultaneously acquiring for each wavelength an image X//(?i) polarized according to said direction and an image X?(?i) polarized according to a direction perpendicular to said direction, X?(?i) being spatially distinct from X//(?i); calculating for each wavelength an intensity image which is a linear combination of X//(?i) and X?(?i), providing an intensity spectrum for each pixel; calculating for each wavelength a polarization contrast image on the basis of an intensity ratio calculated as a function of X//(?i) and of X?(?i), providing a polarization contrast spectrum for each pixel; and calculating a spectro-polarimetric contrast image of the scene, each pixel of this spectro-polarimetric contrast image calculated based on the intensity spectrum and the contrast spectrum of the pixel considered.

Abstract: An ultra-short high-power light pulse source including a first laser pump source (1), a mode-locked laser oscillator (2), a second laser pump source (4), a waveguide (6) capable of inserting spectral phases into the light pulses, and a compressor (8) capable of generating predetermined spectral phases into the light pulses. The waveguide (6) includes an element capable of compensating the predetermined spectral phases generated at least by the compressor (8), the second laser pump source (4) being capable of delivering a second pump light flow (5) having a power PL such that the spectral phases generated by the wave guide (6) are opposed or quasi opposed to the predetermined spectral phases generated by the compressor (8) in order to generate compressed ultra-short light pulses (9) at the output of the compressor (8) with a planar or quasi planar spectral phase.

Abstract: The present invention relates to a method of characterizing a surface and to a device for implementing this method. In particular, this method makes it possible to measure, qualitatively and/or quantitatively, interactions that may be physical, chemical, biochemical or biological.

Abstract: A guided coherent atom source (1) includes elements for generating neutral atoms in a gaseous state (2), elements for cooling the atoms gas (3), elements for generating a magnetic field (4), including an electro-magnetic micro-chip (6) deposited on a surface (18) of a substrate (14), and capable of condensing the atoms in a magnetic trap, elements for generating an electro-magnetic RF field capable of extracting the condensed atoms, optical elements (10) for emitting and directing an optical coherent beam (12) toward the condensed atoms able to guide the condensed atoms, characterized in that the optical elements (10) and the electro-magnetic micro-chip (6) are integrated onto the same substrate (14). An atomic interferometer using such a source is also disclosed.