Abstract: A multi-channel laser source, including: a bus waveguide coupled, at an output end of the bus waveguide, to an output of the multi-channel laser source; a first semiconductor optical amplifier; a first back mirror; a first wavelength-dependent coupler, having a first resonant wavelength, on the bus waveguide; a second semiconductor optical amplifier; a second back mirror; and a second wavelength-dependent coupler, on the bus waveguide, having a second resonant wavelength, different from the first resonant wavelength. In some embodiments the first semiconductor optical amplifier is coupled to the bus waveguide by the first wavelength-dependent coupler, which is nearer to the output end of the bus waveguide than the second wavelength-dependent coupler, the second semiconductor optical amplifier is coupled to the bus waveguide by the second wavelength-dependent coupler, and the first wavelength-dependent coupler is configured to transmit light, at the second resonant wavelength, along the bus waveguide.

Abstract: An optoelectronic device, including: a rib waveguide, the rib waveguide including: a ridge portion, which includes a temperature-sensitive optically active region, and a slab portion, positioned adjacent to the ridge portion; the device further comprising a heater, disposed on top of the slab portion wherein a part of the heater closest to ridge portion is at least 2 ?m away from the ridge portion. The device may also have a heater provided with a bottom cladding layer, and may also include various thermal insulation enhancing cavities.

Abstract: An optoelectronic device, and a method of fabricating an optoelectronic device. The device comprising: a rib waveguide formed of doped silicon, said doped waveguide having a ridge portion, containing an uppermost surface and two sidewall surfaces; and a slab portion, adjacent to the two sidewall surfaces. The device further comprises: a metal contact layer, which directly abuts the uppermost surface and two sidewall surfaces, and which extends along a part of the slab portion so as to provide a Schottky barrier between the metal contact layer and the rib waveguide.

Abstract: A method of manufacturing an optoelectronic device. The manufactured device includes a photonic component coupled to a waveguide. The method comprising: providing a device coupon, the device coupon including the photonic component; providing a silicon platform, the silicon platform comprising a cavity within which is a bonding surface for the device coupon; transfer printing the device coupon onto the cavity, such that a surface of the device coupon directly abuts the bonding surface and at least one channel is present between the device coupon and a sidewall of the cavity; and filling the at least one channel with a filling material via a spin-coating process, to form a bridge coupling the III-V semiconductor based photonic component to the silicon waveguide.

Abstract: An electro-optically active device comprising: a silicon on insulator (SOI) substrate including a silicon base layer, a buried oxide (BOX) layer on top of the silicon base layer, a silicon on insulator (SOI) layer on top of the BOX layer, and a substrate cavity which extends through the SOI layer, the BOX layer and into the silicon base layer, such that a base of the substrate cavity is formed by a portion of the silicon base layer; an electro-optically active waveguide including an electro-optically active stack within the substrate cavity; and a buffer region within the substrate cavity beneath the electro-optically active waveguide, the buffer region comprising a layer of Ge and a layer of GaAs.

Abstract: An optoelectronic device. The device comprising: a multi-layered optically active stack, including one or more layers comprising a lll-V semiconductor material; an input waveguide, arranged to guide light into the stack; and an output waveguide, arranged to guide light out of the stack. The multi-layered optically active stack is butt or edge coupled to the input waveguide and output waveguide.

Abstract: A multi-channel laser source, including: a bus waveguide coupled, at an output end of the bus waveguide, to an output of the multi-channel laser source; a first semiconductor optical amplifier; a first back mirror; a first wavelength-dependent coupler, having a first resonant wavelength, on the bus waveguide; a second semiconductor optical amplifier; a second back mirror; and a second wavelength-dependent coupler, on the bus waveguide, having a second resonant wavelength, different from the first resonant wavelength. In some embodiments the first semiconductor optical amplifier is coupled to the bus waveguide by the first wavelength-dependent coupler, which is nearer to the output end of the bus waveguide than the second wavelength-dependent coupler, the second semiconductor optical amplifier is coupled to the bus waveguide by the second wavelength-dependent coupler, and the first wavelength-dependent coupler is configured to transmit light, at the second resonant wavelength, along the bus waveguide.

Abstract: An optoelectronic device, including: a rib waveguide, the rib waveguide including: a ridge portion, which includes a temperature-sensitive optically active region, and a slab portion, positioned adjacent to the ridge portion; the device further comprising a heater, disposed on top of the slab portion wherein a part of the heater closest to ridge portion is at least 2 ?m away from the ridge portion. The device may also have a heater provided with a bottom cladding layer, and may also include various thermal insulation enhancing cavities.

Abstract: A photonic integrated circuit, an optoelectronic modulator, and a method of modulating light in a photonic integrated circuit are provided. The photonic integrated circuit comprises: an input waveguide which, in use, receives light in a superposition of two polarisation modes of the waveguide; a polarisation splitter, connected to the input waveguide, and configured to provide, at a first output, light in a first polarisation mode of the two polarisation modes of the waveguide and, at a second output, light in a second polarisation mode of the two polarisation modes of the waveguide; a first polarisation rotator, connected to the first output of the polarisation splitter, and configured to rotate light received therefrom from the first polarisation mode to the second polarisation mode; an optoelectronic modulator, having a first modulation waveguide connected to the first polarisation rotator and a second modulation waveguide connected to the second output of the polarisation splitter.

Abstract: A device coupon for use in a hybrid integration process with a silicon platform. The device coupon comprises: an input waveguide, including an input facet; an active waveguide, coupled to the input waveguide, the active waveguide including a III-V semiconductor based electro-optical device; and an output waveguide, configured to couple light between the active waveguide and an output facet. The input waveguide and output waveguide are passive waveguides.

Abstract: A Mach-Zehnder waveguide modulator. In some embodiments, the Mach-Zehnder waveguide modulator includes a first arm including a first optical waveguide, and a second arm including a second optical waveguide. The first optical waveguide includes a junction, and the Mach-Zehnder waveguide modulator further includes a plurality of electrodes for providing a bias across the junction to enable control of the phase of light travelling through the junction.

Abstract: A modulator. In some embodiments, the modulator includes a portion of an optical waveguide, the waveguide including a rib extending upwards from a surrounding slab. The rib may have a first sidewall, and a second sidewall parallel to the first sidewall. The rib may include a first region of a first conductivity type, and a second region of a second conductivity type different from the first conductivity type. The second region may have a first portion parallel to and extending to the first sidewall, and a second portion parallel to the second sidewall. The first region may extend between the first portion of the second region and the second portion of the second region.

Abstract: A photonic chip. In some embodiments, the photonic chip includes a waveguide; and an optically active device comprising a portion of the waveguide. The waveguide may have a first end at a first edge of the photonic chip; and a second end, and the waveguide may have, everywhere between the first end and the second end, a rate of change of curvature having a magnitude not exceeding 2,000/mm2.

Abstract: A method of fabricating a device coupon including a waveguide which is suitable for use in a micro-transfer printing process. The method comprises the steps, on a wafer, of: depositing a lower cladding layer on an uppermost surface of the wafer; providing a silicon nitride guiding layer on an uppermost surface of the lower cladding; depositing an upper cladding over at least an uppermost surface of the silicon nitride guiding layer; providing a tether over the coupon, and etching away a region of the uppermost layer of the wafer located between the lower cladding layer and a substrate of the wafer, thereby leaving the lower cladding layer, silicon nitride guiding layer, and upper cladding layer suspended above the wafer via the tether.

Abstract: A silicon based electro-optically active device and method of producing the same. The silicon based electro-optically active device comprising: a silicon-on-insulator (SOI) waveguide; an electro-optically active waveguide including an electro-optically active stack within a cavity of the SOI waveguide; and a lined channel between the electro-optically active stack and the SOI waveguide, the lined channel comprising a liner; wherein the lined channel is filled with a filling material with a refractive index similar to that of a material forming a sidewall of the cavity, to thereby form a bridge-waveguide in the channel between the SOI waveguide and the electro-optically active stack.

Abstract: A multi-channel laser source, including: a bus waveguide coupled, at an output end of the bus waveguide, to an output of the multi-channel laser source; a first semiconductor optical amplifier; a first back mirror; a first wavelength-dependent coupler, having a first resonant wavelength, on the bus waveguide; a second semiconductor optical amplifier; a second back mirror; and a second wavelength-dependent coupler, on the bus waveguide, having a second resonant wavelength, different from the first resonant wavelength. In some embodiments the first semiconductor optical amplifier is coupled to the bus waveguide by the first wavelength-dependent coupler, which is nearer to the output end of the bus waveguide than the second wavelength-dependent coupler, the second semiconductor optical amplifier is coupled to the bus waveguide by the second wavelength-dependent coupler, and the first wavelength-dependent coupler is configured to transmit light, at the second resonant wavelength, along the bus waveguide.

Abstract: An electro-optically active device comprising: a silicon on insulator (SOI) substrate including a silicon base layer, a buried oxide (BOX) layer on top of the silicon base layer, a silicon on insulator (SOI) layer on top of the BOX layer, and a substrate cavity which extends through the SOI layer, the BOX layer and into the silicon base layer, such that a base of the substrate cavity is formed by a portion of the silicon base layer; an electro-optically active waveguide including an electro-optically active stack within the substrate cavity; and a buffer region within the substrate cavity beneath the electro-optically active waveguide, the buffer region comprising a layer of Ge and a layer of GaAs.

Abstract: A method of operating an optical modulator. The optical modulator having: a rib waveguide which includes a junction which is either a PIN or PN junction, the junction having a breakdown voltage. The method comprising: applying a reverse bias to the junction, so as to operate the optical modulator around the breakdown voltage of the junction; operating the modulator in an avalanche multiplication and/or band-to-band tunnelling mode by increasing the reverse bias past the breakdown voltage.

Abstract: A silicon based photodetector and method of manufacturing the same. The photodetector comprising: a silicon substrate (201); a buried oxide layer (202), above the silicon substrate; and a waveguide (203), above the buried oxide layer. The waveguide (203) includes a silicon, Si, containing region and a germanium tin, GeSn, containing region (209), both located between a first doped region (206) and a second doped region (207) of the waveguide (203), thereby forming a PIN diode. The first doped region (206) and the second doped region (207) are respectively connected to first and second electrodes (210a, 210b), such that the waveguide (203) is operable as a photodetector.

Abstract: A modulator. In some embodiments, the modulator includes a portion of an optical waveguide, the waveguide including a rib extending upwards from a surrounding slab. The rib may have a first sidewall, and a second sidewall parallel to the first sidewall. The rib may include a first region of a first conductivity type, and a second region of a second conductivity type different from the first conductivity type. The second region may have a first portion parallel to and extending to the first sidewall, and a second portion parallel to the second sidewall. The first region may extend between the first portion of the second region and the second portion of the second region.