Abstract: Disclosed is a photodetector which includes, in series along a stacking direction: a first layer forming a substrate of a first semiconductor material; a second layer forming a photoabsorbent layer of a second semiconductor material having a second gap; a third layer forming a barrier layer of a third semiconductor material; and a fourth layer forming a window layer of a fourth semiconductor material, the first material, the third material and the fourth material each having a gap larger than the second gap, the fourth material being n-doped or non-doped and the third material being non-doped or lightly p-doped when the second material is n-doped, and the fourth material being p-doped or non-doped and the third material being non-doped or lightly n-doped when the second material is p-doped.

Abstract: The invention relates to a method for preparing a sol-gel solution which can be used to prepare a barium titanate ceramic doped with hafnium and/or with at least one lanthanide element, comprising the following steps: a) a step to place a first mixture comprising a barium carboxylate and a diol solvent in contact with a second mixture comprising a titanium alkoxide and a hafnium alkoxide and/or an alkoxide of a lanthanide element in a monoalcohol solvent; b) a step to distil the mixture resulting from step a) to remove at least part of the monoalcohol solvent; c) a step to add acetic acid, under heat, to the distilled mixture of step b).

Abstract: A photobioreactor system and a process for its use is illustrated, whereby water and nutrients from multiple sources are balanced (mixed using aeration) to the specific requirements of the particular photosynthetic organism strain used, sterilized, further mixed to balance the system and seeded with the photosynthetic microorganism, e.g. microalgae (dilution of a concentrated stock or added to an existing algal biomass). In accordance with such an embodiment, the algal biomass is then grown for a most efficient number of hours in a totally controlled environment where temperature (using aeration, an internal coil cooling system, or a combination thereof), pH (via CO2 delivery) and light delivery (using internal lighting directly inside the algal biomass) are optimized to the algal strain grown.

Abstract: A photobioreactor system and a process for its use is illustrated, whereby water and nutrients from multiple sources are balanced (mixed using aeration) to the specific requirements of the particular photosynthetic organism strain used, sterilized, further mixed to balance the system and seeded with the photosynthetic microorganism, e.g. microalgae (dilution of a concentrated stock or added to an existing algal biomass). In accordance with such an embodiment, the algal biomass is then grown for a most efficient number of hours in a totally controlled environment where temperature (using aeration, an internal coil cooling system, or a combination thereof), pH (via CO2 delivery) and light delivery (using internal lighting directly inside the algal biomass) are optimized to the algal strain grown.

Abstract: A photobioreactor system and a process for its use is illustrated, whereby water and nutrients from multiple sources are balanced (mixed using aeration) to the specific requirements of the particular photosynthetic organism strain used, sterilized, further mixed to balance the system and seeded with the photosynthetic microorganism, e.g. microalgae (dilution of a concentrated stock or added to an existing algal biomass). In accordance with such an embodiment, the algal biomass is then grown for a most efficient number of hours in a totally controlled environment where temperature (using aeration, an internal coil cooling system, or a combination thereof), pH (via CO2 delivery) and light delivery (using internal lighting directly inside the algal biomass) are optimized to the algal strain grown.

Abstract: The invention relates to a method for preparing a sol-gel solution which can be used to prepare a barium titanate ceramic doped with hafnium and/or with at least one lanthanide element, comprising the following steps: a) a step to place a first mixture comprising a barium carboxylate and a diol solvent in contact with a second mixture comprising a titanium alkoxide and a hafnium alkoxide and/or an alkoxide of a lanthanide element in a monoalcohol solvent; b) a step to distil the mixture resulting from step a) to remove at least part of the monoalcohol solvent; c) a step to add acetic acid, under heat, to the distilled mixture of step b).

Abstract: The invention relates to a pixel of a CMOS imager, the pixel comprising: an infrared photodiode suitable for generating an electric current when it is exposed to an optical radiation having a wavelength greater than 950 nanometers, a conversion circuit able to receive electrons and deliver a voltage with a value varying as a function of the number of received electrons, a first switch connected between the infrared photodiode and the conversion circuit.

Abstract: The invention relates to a method for preparing a material based on metal element(s) oxide(s) on a substrate, comprising the following successive steps: a) depositing, by liquid means, on at least one face of this substrate, at least one layer of a sol-gel precursor solution of the constituent metal element(s) oxide(s) of said material; b) depositing, by liquid means, on said layer deposited in a), at least one layer of a dispersion comprising a powder of metal element(s) oxide(s) and a sol-gel solution identical to or different from that used in step a), said solution being a precursor of the constituent metal element(s) oxide(s) of said material and the powder consisting of constituent metal element(s) oxide(s) of said material; c) heat treating said layers deposited in a) and b) in order to transform them into said material.

Abstract: This optical detector unit is a hybrid unit operating in a given wavelength range and includes, superposed, a first optical detector comprising detecting elements formed in a semiconductor structure, each detecting element being intended for converting a flux of incident photons into an electrical signal; and a first read out circuit, for reading the electrical signal from each detecting element. The optical detector unit furthermore has an imaging system with a second optical detector intended for increasing the operating wavelength range of the optical detector unit and a second read out circuit for reading the electrical signals from the detecting elements of the second optical detector. The first and second read out circuit are integrated together, so as to form a common read out circuit.

Abstract: This optical detector unit is a hybrid unit operating in a given wavelength range and includes, superposed, a first optical detector comprising detecting elements formed in a semiconductor structure, each detecting element being intended for converting a flux of incident photons into an electrical signal; and a first read out circuit, for reading the electrical signal from each detecting element. The optical detector unit furthermore has an imaging system with a second optical detector intended for increasing the operating wavelength range of the optical detector unit and a second read out circuit for reading the electrical signals from the detecting elements of the second optical detector. The first and second read out circuit are integrated together, so as to form a common read out circuit.

Abstract: The invention relates to a method for preparing a material based on metal element(s) oxide(s) on a substrate, comprising the following successive steps: a) depositing, by liquid means, on at least one face of this substrate, at least one layer of a sol-gel precursor solution of the constituent metal element(s) oxide(s) of said material; b) depositing, by liquid means, on said layer deposited in a), at least one layer of a dispersion comprising a powder of metal element(s) oxide(s) and a sol-gel solution identical to or different from that used in step a), said solution being a precursor of the constituent metal element(s) oxide(s) of said material and the powder consisting of constituent metal element(s) oxide(s) of said material; c) heat treating said layers deposited in a) and b) in order to transform them into said material.

Abstract: A semiconductor-based SWIR infrared detector sensitive to wavelengths shorter than about 2.5 microns comprises a stack of semiconductor layers based on III-V materials forming a PIN photodiode. The stack includes a naked electrical contact, called a lower electrical contact, serving as an optical window; and a detection layer sensitive to said wavelengths. The lower contact comprises at least one layer of indirect-bandgap III-V material(s) doped n-type, pseudomorphic or lattice matched with a substrate intended to serve as a temporary substrate possibly being made of a III-V material such as InP or GaAs or of silicon or germanium.

Abstract: The invention relates to a multispectral imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ? lying within a set of wavelengths to which said structure is sensitive, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets (Eij) of four individual detection pixels, a first individual detection pixel (P?1) comprising a first diffraction grating (R?1) sensitive to a first subset of wavelengths, a second individual detection pixel (P?2) comprising a second diffraction grating (R?2) sensitive to a second subset of wavelengths, a third individual detection pixel (P?3) comprising a third diffraction grating (R?3) sensitive to a third subset of wavelengths and a fourth individual detection pixel (P??) not comprising a wavelength-selective diffraction grating, the first, second and third subsets of wavelengths belonging to the set of wavelengths to which said struc

Abstract: A semiconductor-based SWIR infrared detector sensitive to wavelengths shorter than about 2.5 microns comprises a stack of semiconductor layers based on III-V materials forming a PIN photodiode. The stack includes a naked electrical contact, called a lower electrical contact, serving as an optical window; and a detection layer sensitive to said wavelengths. The lower contact comprises at least one layer of indirect-bandgap III-V material(s) doped n-type, pseudomorphic or lattice matched with a substrate intended to serve as a temporary substrate possibly being made of a III-V material such as InP or GaAs or of silicon or germanium.

Abstract: A method of preparing a sol of lead zirconium titanate, known as PZT, of formula PbZrxTi(1?x)O3 with 0.45?x?0.7, comprises the steps of: (a) preparing a concentrated sol in a diol, the sol comprising a titanium-based precursor, a zirconium-based precursor, and a lead-based precursor; (b) placing the concentrated sol at ambient temperature without agitation, until a sol is obtained having a constant viscosity as a function of time; (c) diluting the sol obtained in (b) with a solvent compatible with the diol used in step (a). The sol is useful for preparing PZT-based films for use in the electronics field.

Abstract: The invention relates to a detector comprising a multiple quantum well structure operating on interband or intersubband transitions by absorption of radiation having a wavelength ? having a polarization comprising a component perpendicular to the plane of the multiple quantum well structure, and comprising optical coupling means for coupling said radiation, wherein the coupling means comprise a set of first diffractive lamellar features that are distributed along at least a first direction and a set of second diffractive lamellar features that are distributed along at least a second direction, said first and second directions being mutually perpendicular and lying in a plane parallel to the plane of the multiple quantum well structure.

Abstract: The invention relates to a polarimetric imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ?, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets of four individual pixels, a first pixel comprising a first diffraction grating (RP1) sensitive to a first polarization, a second polarimetric pixel comprising a second diffraction grating (RP2) sensitive to a second polarization orthogonal to the first polarization, a third polarimetric pixel comprising a third diffraction grating (RP3) sensitive to a third polarization oriented at an angle between the first and second polarizations and a fourth pixel not comprising a polarization-selective diffraction rating (R2D).

Abstract: The invention relates to a multispectral imaging device comprising a multiple-quantum-well structure operating on inter-sub-band transitions by absorbing radiation at a wavelength ? lying within a set of wavelengths to which said structure is sensitive, said structure comprising a matrix of individual detection pixels, characterized in that the matrix is organized in subsets (Eij) of four individual detection pixels, a first individual detection pixel (P?1) comprising a first diffraction grating (R?1) sensitive to a first subset of wavelengths, a second individual detection pixel (P?2) comprising a second diffraction grating (R?2) sensitive to a second subset of wavelengths, a third individual detection pixel (P?3) comprising a third diffraction grating (R?3) sensitive to a third subset of wavelengths and a fourth individual detection pixel (P??) not comprising a wavelength-selective diffraction grating, the first, second and third subsets of wavelengths belonging to the set of wavelengths to which said struc

Abstract: The invention relates to an optical coupling structure intended to couple electromagnetic radiation to the surface of a photodetector, wherein a coupling surface paved along mutually perpendicular first and second directions by a set of N series (M1i, M2i, . . . . Mni) of first features, second features, . . . nth features, the features being identical within any one series, the features being distributed along the first and second directions, the distance between the centers of two adjacent features or the inter-reticular distances between two adjacent features being variable. The subject of the invention is also a detector or a laser source comprising said coupling structure.

Abstract: The field of the invention is that of photodetectors (10), and more precisely so-called quantum well photodetectors operating in the medium infrared, known by the acronym QWIP standing for Quantum Well Infrared Photodetector. It is an object of the invention to increase the detectivity of the detectors by significantly reducing the surface area of the detection zone while conserving the incident flux. This result is obtained by arranging a structure (4) or grating on the active zone (31) of the photodetector (10), which couples the incident wave and confines it on the active zone (31). The major features of this structure (4) or this grating are that it comprises patterns or grooves having a first spatial frequency and a second spatial frequency, and also comprising a central defect.