Abstract: For regenerating a binary optical signal (sd, sE2) a monolithic semiconductor component (100) comprises: a saturable absorber structure (3) having a saturable absorber section (31), a first optical waveguide (1, 11 to 16) defining a first guide axis (X) disposed on either side of the section (31), a second optical waveguide (2, 21 to 24) defining a second guide axis (Y) crossing the first axis (X) in the section (31) and disposed on either side of the section (31). The saturable absorber structure has a dimension along the first guide axis greater than its dimension along the second guide axis. The first and second waveguides respectively inject an optical clock signal (c1) and the binary optical signal (sd, sE2). Application to optical transmission systems for regenerating signals in accordance with two different regeneration regimes.

Abstract: The invention relates to a semiconductor optical amplifier including a buried guide active structure (12), characterized in that the guide active structure (12) is subjected to an external stress to render the gain of said amplifier insensitive to the polarization of the light to be amplified, said external stress coming from a force induced by a deposit of a material (50) against a ridge (15) surrounding said guide active structure (12).

Abstract: The invention concerns a semiconductor optical amplifier including at least two amplifier sections (30, 40) respectively favoring a higher gain of the TE mode and the TM mode of polarization of the light to be amplified, said sections each having an active guide structure (12) of the same thickness (e), the amplifier being characterized in that the active guide structure (12) of the two sections (30, 40) is subjected to respective different tension stresses and/or has a different geometry so as to render the overall gain of the amplifier insensitive to the polarization of said light to be amplified, and in that there is no discontinuity of the effective refractive index at the transition between the sections (30, 40).

Abstract: For regenerating a binary optical signal (sd, sE2) a monolithic semiconductor component (100) comprises:

Abstract: In order to be able to use a semiconductor light amplifier of conventional type and operating under gain saturation conditions while nevertheless providing constant gain for an optical signal to be amplified, the device comprises means for producing a compensation light wave and coupling means for injecting the optical signal to be amplified and the compensation light wave into the amplifier. The compensation light wave presents amplitude modulation such that when combined with the optical signal to be amplified the overall amplitude modulation is eliminated or at least attenuated. The device is applicable to optical transmission systems operating at a single wavelength or with wavelength division multiplexing.

Abstract: The invention concerns a semiconductor optical amplifier including at least two amplifier sections (30, 40) respectively favoring a higher gain of the TE mode and the TM mode of polarization of the light to be amplified, said sections each having an active guide structure (12) of the same thickness (e), the amplifier being characterized in that the active guide structure (12) of the two sections (30, 40) is subjected to respective different tension stresses and/or has a different geometry so as to render the overall gain of the amplifier insensitive to the polarization of said light to be amplified, and in that there is no discontinuity of the effective refractive index at the transition between the sections (30, 40).

Abstract: The invention relates to a semiconductor optical amplifier including a buried guide active structure (12), characterized in that the guide active structure (12) is subjected to an external stress to render the gain of said amplifier insensitive to the polarization of the light to be amplified, said external stress coming from a force induced by a deposit of a material (50) against a ridge (15) surrounding said guide active structure (12).

Abstract: The invention relates to a semi-conductor optical amplifier comprising an active waveguide and a laser oscillator structure framing the active waveguide, characterized in that it includes at least one input for control of the gain at the threshold of the said laser structure to enable adjustment of the value of the amplifier's gain. This amplifier is intended to be used in an optical system which includes means of regulation capable of acting on the control inputs of the amplifier in response to the optical power of the carrier wave of an output signal to enable adjustment of the value of the amplifier's gain. This optical system makes it possible particularly to obtain power equalization of a signal at the entry to a telecommunication system.

Abstract: The invention relates to a semi-conductor optical amplifier insensitive to the polarization of light. The active layer (20) of this amplifier is made up of an alternating series of solid sub-layers alternately under tensile stress (21) and compressive stress (22) and having the same forbidden band-width. The sub-layers under tensile stress (21) favour the propagation of the TM mode of polarization of light and the sub-layers under compression (22) favour the propagation of the TE mode of polarization of light. In addition, the thicknesses of the sub-layers have values which ensure equal gains G(TE) and G(TM) for the active layer.

Abstract: An active structure in the semiconductor die of an amplifier or converter includes a plurality of stacked active layers with different compositions. The different compositions lead to a spectral offset between the respective gain bands of the layers which widens the gain band of the amplifier or the optical bandwidth of the converter. Applications include fiber optic telecommunication networks.

Abstract: The invention relates to wavelength converters for optical signals, as used in telecommunications, in particular for routing signals. The invention relates in particular to a wavelength converter including an interferometer structure for delivering an output optical signal, in which converter first and second branches, including at least one first semiconductor optical amplifier, are coupled to input peripheral semiconductor optical amplifiers and/or to an output peripheral semiconductor optical amplifier, wherein the structure of the active waveguide of at least one peripheral amplifier is so designed that it has a ratio of active area to confinement factor greater than that of the active waveguide of said first amplifier.

Abstract: The invention concerns a semiconductor optical amplifier. The optical guide structure of this amplifier comprises a rectangular cross-section active stripe (12). Its material is homogeneous and it is subjected to a tensile strain sufficient to render the amplifier insensitive to the polarisation of the light to be amplified.The invention finds an application in optical telecommunications.

Abstract: From a top face of a semiconductor structure of the III-V type, inter-diffusion of elements between the wells and the barriers of an internal quantum structure is hot induced. The inter-diffusion is performed in one segment of the structure only, namely a segment in which the characteristic wavelength is to be shifted so as to constitute an amplitude modulator, another segment of the structure including a Bragg grating so as to constitute a laser emitter. In accordance with the invention, the inter-diffusion is induced by a layer of indium maintained in contact with the top face by means of a dielectric encapsulation layer. The invention is applicable in particular to optical telecommunications.

Abstract: A portion of the surface of the first structure is protected by an oxide deposit, and the non-protective layers are etched down to a stop layer. The layers in the etched zone are then built up by molecular beam epitaxy, and one of the built-up layers is given a composition that is different from the composition of the corresponding adjacent layer in the first structure. The method is applicable to fabricating an integrated semiconductor comprising both a laser and a modulator.