Abstract: A method for forming a Bragg reflector includes after forming first trenches in the stack, which are intended to form structures of the distributed Bragg reflector, forming a sacrificial interlayer at least in the first trenches, depositing a second masking layer at least inside the first trenches, forming second trenches intended to form sidewalls of the laser, removing the second masking layer from inside the first trenches, removing said sacrificial interlayer so as to remove, by lift-off, residues of the second masking layer that remain inside the first trenches, and filling said first trenches with at least one metal material.

Abstract: An optical particle detector including at least one channel intended to receive a fluid carrying at least one particle, and across which light rays are intended to pass such that the light rays are partially scattered by the at least one particle, a plurality of photodetectors capable of receiving said scattered light rays, wherein the detector includes at least one optical waveguide configured to collect, at least at one entrance of the waveguide, light rays that were not scattered by the at least one particle and having crossed the channel, and to reinject the unscattered light rays into the channel through at least one exit of the waveguide.

Abstract: A device for the photoacoustic characterisation of a gaseous substance, includes a chamber intended to contain the gaseous substance to characterise and into which a light beam is injected. The chamber is delimited, inter alia, by an inner face, on which a part of the light beam is reflected. This inner face is etched so as to have recesses, each recess being delimited laterally by a lateral surface of which a part at least is tilted, with respect to an average plane of the inner face, by a given tilt angle (?).

Abstract: A photoacoustic detecting device to be applied, via a contact face, against a medium to be analyzed, is disclosed. The device includes: a hollow cavity that opens onto a contact aperture, the contact aperture being produced in the contact face; a pulsed or amplitude-modulated light source configured to emit, when activated, an incident light beam, in an emission spectral band, through the cavity, to the contact aperture; and an acoustic transducer connected to the cavity and configured to detect a photoacoustic wave extending through the cavity. Under the effect of illuminating the medium by the incident light beam, the acoustic transducer detects an acoustic wave produced by heating the medium. The cavity includes a membrane extending through the cavity, facing the contact face. The membrane is bounded by a lower face and an upper face. The membrane includes through-apertures produced between the lower face and the upper face.

Abstract: An optical particle detector is configured to simultaneously detect at least two particles within a useful detection volume. The detector includes a retina capable of receiving light rays scattered by the particles and a dark reticle interposed between the useful detection volume and the retina. The dark reticle includes at least one optical aperture allowing a passage towards the retina of a part of first scattered light rays and of a part of second scattered light rays, and an opaque surface on a periphery of the at least one aperture, preventing a passage towards the retina of another part of the first and second scattered light rays so as to project onto the retina first and second scattering diagrams separated from each other.

Abstract: A method for analysing a sample uses a resonant support having a surface on which a plurality of separated photonic crystals extends. At least two crystals are configured to capture the same analyte. A resonance wavelength associated with each crystal varies with an amount of analyte in contact with the crystal. The wavelengths define a resonance spectral band between 200-1500 nm. The transmission/reflection of the light is maximum at an associated resonance wavelength. The method includes: illuminating the support in the resonance spectral band, the intensity of the lamination being variable in band; acquiring a measurement image using an image sensor, the image having different regions-of-interest each optically coupled to a photonic crystal; using a reference image representative of an image acquired by the image sensor, when the support is illuminated in the resonance spectral band in a reference configuration; and comparing the measurement image with the reference image.

Abstract: A method for analysing a sample uses a resonant support. The sample extends on the support having a surface on which a plurality of separated photonic crystals extend. The sample extends between a light source and the crystals, wherein a resonance wavelength is associated with each crystal addressing the analyte and the wavelengths of the crystals define a resonance spectral band extending between 2 ?m and 20 ?m. The transmission or reflection of light by each crystal addressing the analyte is maximum at the associated resonance wavelength. The method includes illuminating the support by the light source, the light source emitting an illumination lightwave defining an illumination spectral band which at least partially covers the resonance spectral band, such that a plurality of crystals are simultaneously illuminated; acquiring an image of the support, and then determining the presence of the analyte in the sample from the image.

Abstract: A photonic integrated circuit for an interferometric sensor includes a first waveguide called sensitive arm wherein a first portion of the light radiation is propagated, the sensitive arm being exposed to a first ambient medium and to at least one compound to be detected inducing a modification of the local refractive index perceived by the evanescent part of the electromagnetic field of the first portion of the light radiation, and a second waveguide called reference arm wherein a second portion of the light radiation is propagated, an encapsulation layer encapsulating the reference arm, the encapsulation layer being impermeable to the compound or compounds to be detected, so that the reference arm is exposed only to a second ambient medium, substantially of the same nature as the first ambient medium and without the compound to be detected and interferometric sensor comprising a photonic integrated circuit according to the invention.

Abstract: Photoacoustic detecting device (1) intended to be applied, via a contact face (3), against a medium (2) to be analysed, the device comprising: a hollow cavity (20) that opens onto a contact aperture (22), the contact aperture being produced in the contact face; a pulsed or amplitude-modulated light source (10) configured to emit, when it is activated, an incident light beam (11), in an emission spectral band (LA), through the cavity (20), to the contact aperture; an acoustic transducer (28) connected to the cavity, and configured to detect a photoacoustic wave (12) extending through the cavity; such that, under the effect of an illumination of the medium by the incident light beam, the acoustic transducer detects an acoustic wave produced by heating of the medium (2); wherein the cavity comprises a membrane extending through the cavity, facing the contact face; the membrane is bounded by a lower face (23i) and an upper face (23s), the membrane comprising through-apertures (23o) produced between the lowe

Abstract: A laser includes a distributed Bragg minor and is configured to emit monochromatic light radiation along a longitudinal direction. The laser has layers, stacked along a first transverse direction normal to the longitudinal direction and made of III-V materials, including an active region configured to emit the radiation. The mirror is formed by periodic lateral corrugations which extend mainly along the longitudinal direction and having a dimension along a second transverse direction normal to the longitudinal direction. The lateral corrugations of the Bragg minor extend from a top surface of the waveguide pattern along the first transverse direction on a height strictly less than the depth, at which the active region is located starting from the top surface, such that a portion of lateral flanks of the waveguide is free of any lateral corrugations at the active region.

Abstract: A laser is provided, including: a distributed Bragg mirror; a waveguide, the laser to emit light radiation along a longitudinal direction x, and the waveguide formed at least in part in a stack of layers made of III-V materials including at least one active region to emit the light radiation, the mirror including lateral corrugations distributed periodically along the direction x in a period ?, the corrugations being carried by at least a lateral plane xz defined by the direction x and a first transverse direction z normal to the direction x, the corrugations having a dimension d along a second transverse direction y normal to the direction x; and a top electrode arranged on the waveguide along the direction z, the corrugations being partly located at lateral flanks of the top electrode, extending parallel to the plane xz, and extending only on the lateral flanks of the top electrode.

Abstract: A method for forming a Bragg reflector includes after forming first trenches in the stack, which are intended to form structures of the distributed Bragg reflector, forming a sacrificial interlayer at least in the first trenches, depositing a second masking layer at least inside the first trenches, forming second trenches intended to form sidewalls of the laser, removing the second masking layer from inside the first trenches, removing said sacrificial interlayer so as to remove, by lift-off, residues of the second masking layer that remain inside the first trenches, and filling said first trenches with at least one metal material.

Abstract: A particle detector includes at least one resonant cavity partially formed at least by a first reflector, a second reflector disposed at a distance from the first reflector and a channel located between the first and second reflectors, the channel being intended to receive at least one fluid comprising particles and to receive at least one light radiation; and at least one detection system having at least one photodetector. The particle detector is configured so that a portion of the light radiation present in the channel escapes from the cavity throughout the second reflector and reaches the detection system, thereby enabling the at least one photodetector to detect leakage of the cavity. The second reflector is a photonic crystal membranes PCM based reflector.

Abstract: An optical particle detector including at least one channel intended to receive a fluid carrying at least one particle, and across which light rays are intended to pass such that the light rays are partially scattered by the at least one particle, a plurality of photodetectors capable of receiving said scattered light rays, wherein the detector includes at least one optical waveguide configured to collect, at least at one entrance of the waveguide, light rays that were not scattered by the at least one particle and having crossed the channel, and to reinject the unscattered light rays into the channel through at least one exit of the waveguide.

Abstract: A method for producing a waveguide including a germanium-based core and a cladding is provided, the method including a step of “low temperature” depositing of a shell after forming the core by engraving, such that the deposition temperature is less than 780° C., followed by a step of “high temperature” depositing of a thick encapsulation layer. The shell and the encapsulation layer at least partially form the cladding of the waveguide. Optionally, a step of annealing under hydrogen at a “low temperature”, less than 750° C., precedes the deposition of the shell. These “low temperature” annealing and depositing steps advantageously make it possible to avoid a post-engraving alteration of the free surfaces of the core during the forming of the cladding which is less germanium-rich.

Abstract: A device for the photoacoustic characterisation of a gaseous substance, includes a chamber intended to contain the gaseous substance to characterise and into which a light beam is injected. The chamber is delimited, inter alia, by an inner face, on which a part of the light beam is reflected. This inner face is etched so as to have recesses, each recess being delimited laterally by a lateral surface of which a part at least is tilted, with respect to an average plane of the inner face, by a given tilt angle (?).

Abstract: A photonic integrated circuit for an interferometric sensor includes a first waveguide called sensitive arm wherein a first portion of the light radiation is propagated, the sensitive arm being exposed to a first ambient medium and to at least one compound to be detected inducing a modification of the local refractive index perceived by the evanescent part of the electromagnetic field of the first portion of the light radiation, and a second waveguide called reference arm wherein a second portion of the light radiation is propagated, an encapsulation layer encapsulating the reference arm, the encapsulation layer being impermeable to the compound or compounds to be detected, so that the reference arm is exposed only to a second ambient medium, substantially of the same nature as the first ambient medium and without the compound to be detected and interferometric sensor comprising a photonic integrated circuit according to the invention.

Abstract: A method for producing a waveguide including a germanium-based core and a cladding is provided, the method including a step of “low temperature” depositing of a shell after forming the core by engraving, such that the deposition temperature is less than 780° C., followed by a step of “high temperature” depositing of a thick encapsulation layer. The shell and the encapsulation layer at least partially form the cladding of the waveguide. Optionally, a step of annealing under hydrogen at a “low temperature”, less than 750° C., precedes the deposition of the shell. These “low temperature” annealing and depositing steps advantageously make it possible to avoid a post-engraving alteration of the free surfaces of the core during the forming of the cladding which is less germanium-rich.

Abstract: The invention relates to a method for manufacturing a waveguide (40) including a semiconducting junction (23). The method comprises the following steps: providing a support (10) comprising a semiconducting layer (20) having a first part (21) of a first conductivity type ; protecting the first part ; selectively implanting a second conductivity-type dopants in a second part (22) of the semiconducting layer (20) adjacent to the first part (21, 221). The concentration of second conductivity-type dopants in the second part (22, 222) is greater than the one of first conductivity-type dopants in the first part (21, 221).

Abstract: The invention relates to a method for manufacturing a waveguide (40) including a semiconducting junction (23). The method comprises the following steps: providing a support (10) comprising a semiconducting layer (20) having a first part (21) of a first conductivity type ; protecting the first part ; selectively implanting a second conductivity-type dopants in a second part (22) of the semiconducting layer (20) adjacent to the first part (21, 221). The concentration of second conductivity-type dopants in the second part (22, 222) is greater than the one of first conductivity-type dopants in the first part (21, 221).