A photonic integrated circuit including first and second opto-electronic devices that are fabricated on a semiconductor wafer having an epitaxial layer stack including an n-type indium phosphide-based contact layer that is provided with at least one selectively p-type doped tubular-shaped region for providing an electrical barrier between respective n-type contact regions of the first and second opto-electronic devices that are optically interconnected by a passive optical waveguide that is fabricated in a non-intentionally doped waveguide layer including indium gallium arsenide phosphide, the non-intentionally doped waveguide layer being arranged on top of the n-type contact layer, wherein a first portion of the at least one selectively p-type doped tubular-shaped region is arranged underneath the passive optical waveguide between the first and second opto-electronic devices. An opto-electronic system including the photonic integrated circuit.

A photonic integrated circuit (PIC) in which some optical waveguides have laterally tilted waveguide cores used to implement passive polarization-handling circuit elements, e.g., suitable for processing polarization-division-multiplexed optical communication signals. Different sections of such waveguide cores may have continuously varying or fixed lateral tilt angles. Different polarization-handling circuit elements can be realized, e.g., using different combinations of end-connected untilted and laterally tilted waveguide-core sections. In some embodiments, laterally tilted waveguide cores may incorporate multiple-quantum-well structures and be used to implement active circuit elements. At least some embodiments beneficially lend themselves to highly reproducible fabrication processes, which can advantageously be used to achieve a relatively high yield of the corresponding PICs during manufacture.

A Distributed Feedback Laser (DFB) mounted on a Silicon Photonic Integrated Circuit (Si PIC), the DFB having a longitudinal length which extends from a first end of the DFB laser to a second end of the DFB laser, the DFB laser comprising: an epi stack, the epi stack comprising: one or more active material layers; a layer comprising a partial grating, the partial grating extending from the second end of the DFB laser, only partially along the longitudinal length of the DFB laser such that it does not extend to the first end of the DFB laser; a highly reflective medium located at the first end of the DFB laser; and a back facet located at the second end of the DFB laser.

A photonic chip including an optical coupler capable of transferring an optical signal between a first waveguide made of III-V material and a second waveguide made of silicon, this optical coupler including a first extension made of III-V material which extends the core of the first waveguide, a second extension made of silicon which extends the core of the second waveguide, and a SiGe inclusion buried inside of the second extension, this inclusion being made of SiGe whose chemical formula is Si.sub.1-xGe.sub.x, where x is in the range between 0.2and 0.5, and being optically coupled, on a first side, to the first waveguide and, on a second opposite side, to the second waveguide.

An optical waveguide is an optical waveguide including a semiconductor quantum well structure, the optical waveguide including a first region in which the semiconductor quantum well structure is not disordered and a second region in which the semiconductor quantum well structure is disordered. The first region has a first bandgap wavelength, the second region has a second bandgap wavelength, and a region in which the semiconductor quantum well structure is disordered in such a manner that a bandgap wavelength continuously decreases from the first bandgap wavelength to the second bandgap wavelength is provided between the first region and the second region.

Embodiments of the invention describe optical devices including a III-V slab having a taper including a first region and a second region smaller than the first. Said first region receives light and confines an optical mode of the received light; thus, as opposed to the prior art solutions, said III-V regions of optical devices perform the optical function of mode confinement. Embodiments of the invention further describe optical devices including a silicon slab to receive light from said III-V slab, and having a taper including a first silicon region and a second silicon region smaller than the first. Said first region receives light and confines an optical mode of the received light. Thus, embodiments of the invention describe optical devices created with a low loss transition from hybrid regions to silicon regions with fewer restrictions on the design of the silicon waveguides and the III-V waveguides.

The fabrication of a first waveguide made of stoichiometric silicon nitride, of a second waveguide made of crystalline semiconductor material and of at least one active component optically coupled to the first waveguide via the second waveguide. The method includes: a) the formation of an aperture which passes through an encapsulation layer of the first waveguide and emerges in or on a substrate made of monocrystalline silicon, then b) the deposition by epitaxial growth of a crystalline seeding material inside the aperture until this crystalline seeding material forms a crystalline seed on a top face of the encapsulation layer, then c) a lateral epitaxy, of a crystalline semiconductor material from the crystalline seed formed to form a layer made of crystalline semiconductor material wherein the second waveguide is then produced.

An example method of forming a deterministic thin film from a crystal substrate is described herein. The method can include implanting ions into a surface of the crystal substrate to form a thin film crystal layer, and bonding the crystal substrate and a handle substrate to form a bilayer bonding interface between the crystal substrate and the handle substrate. The method can also include exfoliating the thin film crystal layer from the crystal substrate, patterning the thin film crystal layer to define a deterministic thin film, etching one or more trenches in the thin film crystal layer, etching the bilayer bonding interface via the one or more trenches, and releasing the deterministic thin film from the handle substrate.

A device, such as an electroabsorption modulator, can modulate a light intensity by controllably absorbing a selectable fraction of the light. The device can include a substrate. A waveguide positioned on the substrate can guide light. An active region positioned on the waveguide can receive guided light from the waveguide, absorb a fraction of the received light, and return a complementary fraction of the received light to the waveguide. Such absorption produces heat, mostly at an input portion of the active region. The input portion of the active region can be thermally coupled to the substrate, which can dissipate heat from the input portion, and can help avoid thermal runaway of the device. The active region can be thermally isolated from the substrate away from the input portion, which can maintain a relatively low thermal mass for the active region, and can increase efficiency when heating the active region.

A device, such as an electroabsorption modulator, can modulate a light intensity by controllably absorbing a selectable fraction of the light. The device can include a substrate. A waveguide positioned on the substrate can guide light. An active region positioned on the waveguide can receive guided light from the waveguide, absorb a fraction of the received light, and return a complementary fraction of the received light to the waveguide. Such absorption produces heat, mostly at an input portion of the active region. The input portion of the active region can be thermally coupled to the substrate, which can dissipate heat from the input portion, and can help avoid thermal runaway of the device. The active region can be thermally isolated from the substrate away from the input portion, which can maintain a relatively low thermal mass for the active region, and can increase efficiency when heating the active region.