An electroabsorption modulator. The modulator comprising an SOI waveguide; an active region, the active region comprising a multiple quantum well (MQW) region; and a coupler for coupling the SOI waveguide to the active region. The coupler comprising: a transit waveguide coupling region; a buffer waveguide coupling region; and a taper region; wherein, the transit waveguide coupling region couples light between the SOI waveguide and the buffer waveguide coupling region; and the buffer waveguide coupling region couples light between the transit waveguide region and the active region via the taper region.

A method of providing electrical isolation between subsections in a waveguide structure for a photonic integrated device, the structure comprising a substrate, a buffer layer and a core layer, the buffer layer being located between the substrate and the core and comprising a dopant of a first type, the first type being either n-type or p- type, the method comprising the steps of prior to adding any layer to a side of the core layer opposite to the buffer layer: selecting at least one area to be an electrical isolation region, applying a dielectric mask to a surface of the core layer opposite to the buffer layer, with a window in the mask exposing an area of the surface corresponding to the selected electrical isolation region, implementing diffusion of a dopant of a second type, the second type being of opposite polarity to the first type, and allowing the dopant of the second type to penetrate to the substrate to form a blocking junction.

A semiconductor device may include a substrate having waveguides thereon, and a superlattice overlying the substrate and waveguides. The superlattice may include stacked groups of layers, with each group of layers comprising a stacked base semiconductor monolayers defining a base semiconductor portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions. The semiconductor device may further include an active device layer on the superlattice including at least one active semiconductor device.

A method for making a semiconductor device may include forming a plurality of waveguides on a substrate, and forming a superlattice overlying the substrate and waveguides. The superlattice may include a plurality of stacked groups of layers, with each group of layers comprising a plurality of stacked base semiconductor monolayers defining a base semiconductor portion, and at least one non-semiconductor monolayer constrained within a crystal lattice of adjacent base semiconductor portions. The method may further include forming an active device layer on the superlattice comprising at least one active semiconductor device.

The present invention relates to a semiconductor optical amplifier, the semiconductor optical amplifier including: a plurality of optical amplification regions arranged in series; a passive waveguide region provided between optical amplification regions; and first and second electrodes provided on an upper surface of each of the optical amplification regions. The passive waveguide region electrically insulates between the first electrodes and between the second electrodes of the adjacent optical amplification regions and optically connects the adjacent optical amplification regions. The semiconductor optical amplifier electrically connects the first electrode and the second electrode of the respective adjacent optical amplification regions so that the plurality of optical amplification regions are electrically connected in cascade, and feeds power to the optical amplification regions at both ends of arrangements of the plurality of optical amplification regions thereby driving the plurality of optical amplification regions.

An optoelectronic device and an array comprising a plurality of the same. The device(s) comprising: an optically active region with an electrode arrangement for applying an electric field across the optically active region; a first curved waveguide, arranged to guide light into the optically active region; and a second curved waveguide, arranged to guide light out of the optically active region; wherein the first curved waveguide and the second curved waveguide are formed of a material having a different band-gap to a band-gap of the optically active region, and wherein the overall guided path formed by the first curved waveguide, the optically active region and the second curved waveguide is U-shaped.

The object of the invention is a phase modulator including a modulation guide intended to guide die propagation of a light flow, said guide comprising a PN junction extending mainly along the main axis of propagation according to an oscillating continuous function. Advantageously, the oscillating continuous function is defined in such a way that the PN junction covers at least 50% of the light flow between the input and the output of the modulation guide. According to one possibility, the continuous function is sinusoidal. The object of the invention is also a switch and an intensity modulator each comprising a phase modulator.

In an embodiment, a network system comprises a plurality of nodes and a plurality of optical amplifiers. A first node comprises a first transmitter configured to send a wavelength-division-multiplexed optical signal and a first receiver configured to receive a wavelength-division-multiplexed optical signal, and the second node comprises a second transmitter configured to send a wavelength-division-multiplexed optical signal and a second receiver configured to receive a wavelength-division-multiplexed optical signal. The first transmitter and the second transmitter are optically connected to an input of the first optical amplifier and an input of the second optical amplifier, respectively, and the first receiver and the second receiver are optically connected to an output of the first optical amplifier and an output of the second optical amplifier, respectively. Each of the first photoreceiver and the second photoreceiver comprises a photoreceiver and a reception circuit. The photoreceiver is electrically connected, by flip chip connection, to a reception circuit. A reception circuit is configured not to comprise a transimpedance amplifier.

In an embodiment, a phase shifter includes: a light input end; a light output end; a p-type semiconductor material, and an n-type semiconductor material contacting the p-type semiconductor material along a boundary area, wherein the boundary area is greater than a length from the light input end to the light output end multiplied by a core width of the phase shifter.

An electroabsorption modulator. The modulator comprising an SOI waveguide; an active region, the active region comprising a multiple quantum well (MQW) region; and a coupler for coupling the SOI waveguide to the active region. The coupler comprising: a transit waveguide coupling region; a buffer waveguide coupling region; and a taper region; wherein, the transit waveguide coupling region couples light between the SOI waveguide and the buffer waveguide coupling region; and the buffer waveguide coupling region couples light between the transit waveguide region and the active region via the taper region.