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 process for fabricating a heterostructure includes at least one elementary structure made of III-V material on the surface of a silicon-based substrate successively comprising: producing a first pattern having at least a first opening in a dielectric material on the surface of a first silicon-based substrate; a first operation for epitaxy of at least one III-V material so as to define at least one elementary base layer made of III-V material in the at least first opening; producing a second pattern in a dielectric material so as to define at least a second opening having an overlap with the elementary base layer; a second operation for epitaxy of at least one III-V material on the surface of at least the elementary base layer made of III-V material(s) so as to produce the at least elementary structure made of III-V material(s) having an outer face; an operation for transferring and assembling the at least photonic active elementary structure via its outer face, on an interface that may comprise passive elements and/or active elements, the interface being produced on the surface of a second silicon-based substrate; removing the first silicon-based substrate and the at least elementary base layer located on the elementary structure.

Temperature measurements of photonic circuit components may be performed optically, exploiting a temperature-dependent spectral property of the photonic device to be monitored itself, or of a separate optical temperature sensor placed in its vicinity. By facilitating measurements of the temperature of the individual photonic devices rather than merely the photonic circuit at large, such optical temperature measurements can provide more accurate temperature information and help improve thermal design.

A photonic integrated circuit (PIC) includes a semiconductor substrate, one or more passive components, and one or more active components. The one or more passive components are fabricated on the semiconductor substrate, wherein the passive components are fabricated in a III-V type semiconductor layer. The one or more active components are fabricated on top of the one or more passive components, wherein optical signals are communicated between the one or more active components via the one or more passive components.

A multi-level semiconductor device, the device including: a first level including integrated circuits; a second level including a structure designed to conduct electromagnetic waves, where the second level is disposed above the first level, where the integrated circuits include single crystal transistors; and an oxide layer disposed between the first level and the second level, where the integrated circuits include at least one processor, where the second level is bonded to the oxide layer, and where the bonded includes oxide to oxide bonds.

Disclosed is a photonic structure and associated method. The structure includes a closed-curve waveguide having a first height, as measured from the top surface of an insulator layer, and an outer curved sidewall that extends essentially vertically the full first height (e.g., to minimize signal loss). The structure includes a closed-curve thermal coupler and a heating element. The closed-curve thermal coupler is thermally coupled to and laterally surrounded by the closed-curve waveguide and has a second height that is less than the first height. In some embodiments, the closed-curve waveguide and the closed-curve thermal coupler are continuous portions of the same semiconductor layer having different thicknesses. The heating element is thermally coupled to the closed-curve thermal coupler and thereby indirectly thermally coupled to the closed-curve waveguide. Thus, the heating element is usable for thermally tuning the closed-curve waveguide via the closed-curve thermal coupler to minimize any temperature-dependent resonance shift (TDRS).

A waveguide component includes a waveguide, which is at least partially transparent or translucent with respect to light and is set up in such a way that light can be conducted at least partially through the waveguide. The waveguide includes a waveguide core, a first casing region, and a second casing region. The waveguide core is formed from one or more spatially separated elements of at least one waveguide core material. The first casing region, which includes at least one electro-optical material, interacts with light guided in the waveguide. The first casing region is disposed around the one or more elements of the waveguide core. The second casing region includes at least one dielectric material. The second casing region is arranged around the first casing region and/or the waveguide core. The waveguide component further includes at least two line regions that are at least partially electrically conductive.

Structures for a coupler and methods of forming a structure for a coupler. A structure for a directional coupler may include a first waveguide core having one or more first airgaps and a second waveguide core including one or more second airgaps. The one or more second airgaps are positioned in the second waveguide core adjacent to the one or more first airgaps in the first waveguide core. A structure for an edge coupler is also provided in which the waveguide core of the edge coupler includes one or more airgaps.

Optical beam forming at the inputs/outputs of a photonic chip and to the spectral broadening of the light coupled to the chip. The photonic chip comprises an optical waveguide layer supported on a substrate. The chip includes an optical waveguide structure made of silicon and a coupling surface grating. The photonic chip has a front face on the side facing the coupling surface grating and a rear face on the side facing the substrate. A reflecting collimation structure is integrated in the rear face to modify the mode size of an incident light beam. The coupling surface grating is designed to receive light from the optical waveguide structure and to form a light beam directed to the reflecting collimation structure. The invention further relates to the method for producing such a chip.

There is provided an optical waveguide device including: a substrate; an optical waveguide formed on the substrate; and a working electrode that controls a light wave propagating through the optical waveguide, in which the working electrode includes a first base layer made of a first material, a first conductive layer on the first base layer, a second base layer made of a second material different from the first material, which is on the first conductive layer, and a second conductive layer on the second base layer, and an edge of the second base layer is covered with the second conductive layer, in a cross-section perpendicular to an extending direction of the optical waveguide.