摘要:
In the field of narrow linewidth laser sources and a laser device that comprises a laser source and a waveguide of determined refractive index with which it is coupled, a waveguide is single-mode and includes at least four reflectors in the form of trenches etched into the waveguide and irregularly distributed along the waveguide, the distance separating two neighbouring reflectors being above 1 μm, and the waveguide and the laser source have respective lengths such that the length of waveguide over which the reflectors are located is greater than the length of the laser source itself.
摘要:
A stabilised gain semiconductor optical amplifier (CG-SOA) includes and active waveguide (1) comprising an amplification medium (2), extending in longitudinal (Z), lateral (X) and vertical (Y) directions, and coupled to a laser oscillation structure comprising at least two resonant cavities (13, 14) extending in first (D1) and second (D2) directions which are different from the longitudinal direction (Z) of the active waveguide (1) and arranged in such a way as to permit the establishment of laser oscillations having at least two different relaxation oscillation frequencies.
摘要:
An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.
摘要:
An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.
摘要:
An external cavity tunable laser includes a gain median module to generate a broadband optical spectrum covering a predetermined wavelength range; a collimate lens turning a diverging beam into a collimated beam; a pair of etalons to tune frequency; an actuator to adjust an external cavity optical pathlength; a bandpass filter to block one or more frequencies outside the predetermined wavelength range; a beam splitter to split a percentage of the beam to a photodetector; a reflection mirror for feedback to gain median waveguide; an isolator for preventing reflecting light back to the external cavity; and a hermetically sealed housing less than 0.15 cubic centimeters.
摘要:
A stabilised gain semiconductor optical amplifier (CG-SOA) includes and active waveguide (1) comprising an amplification medium (2), extending in longitudinal (Z), lateral (X) and vertical (Y) directions, and coupled to a laser oscillation structure comprising at least two resonant cavities (13, 14) extending in first (D1) and second (D2) directions which are different from the longitudinal direction (Z) of the active waveguide (1) and arranged in such a way as to permit the establishment of laser oscillations having at least two different relaxation oscillation frequencies.
摘要:
In a process for fabrication of an optical slot waveguide on silicon, a thin single-crystal silicon film is deposited on a substrate covered with an insulating buried layer; a local thermal oxidation is carried out over the entire depth of the thin single-crystal silicon film in order to form an insulating oxidized strip extending along the desired path of the waveguide; an insulating or semi-insulating layer is deposited on the silicon film; two openings having vertical sidewalls are excavated over the entire thickness of this insulating or semi-insulating layer, said openings being separated by a narrow gap constituting an insulating or semi-insulating vertical wall that will be the material of the slot; single-crystal silicon is grown in the openings and right to the edges of the insulating or semi-insulating wall; and then the upper part of the silicon is etched in order to complete the geometry of the waveguide.
摘要:
An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.
摘要:
The field of the invention is that of the semiconductor optical devices used in particular for fibre-optic telecommunications. To function efficiently, a certain number of semiconductor devices require the use of light polarized in a given polarization state. When knowledge of the polarization the state is lost, the optical element according to the invention makes it possible to polarize the light again in a known polarization state. By using two of these elements in combination with a coupler, it is possible to produce a device which fulfils the same function as a polarization splitter. This optical assembly delivers two output signals whose polarization states are the projections of the initial polarization onto two orthogonal axes. The main advantage of these devices is that they are produced using polarization rotators based on photonic crystals, and they can consequently be integrated easily into semiconductor devices, which the use of discrete polarizers does not allow.
摘要:
An photonic device, comprising one section of a material which is different from the material of another section such that the two sections present different optical birefringent index values. This causes a first set of polarization modes to move in a spectral space with a different velocity than a second set of polarization modes. A bias current, or voltage, is used for controlling the overall birefringence effect in the device. The biasing for controlling the birefringence effect is performed such the TE modes and the TM modes of the device are made to coincide in their respective spectral position. Thus the device is made insensitive, or presents substantially reduced sensitivity, to the polarization of any incoming optical signal.