Abstract: An optoelectronic device and method of making the same. The device comprising: a substrate; an epitaxial crystalline cladding layer, on top of the substrate; and an optically active region, above the epitaxial crystalline cladding layer; wherein the epitaxial crystalline cladding layer has a refractive index which is less than a refractive index of the optically active region, such that the optical power of the optoelectronic device is confined to the optically active region.

Abstract: An optoelectronic device and method of making the same. The device comprising: a substrate; an epitaxial crystalline cladding layer, on top of the substrate; and an optically active region, above the epitaxial crystalline cladding layer; wherein the epitaxial crystalline cladding layer has a refractive index which is less than a refractive index of the optically active region, such that the optical power of the optoelectronic device is confined to the optically active region.

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: An optoelectronic device comprising: a silicon-on-insulator (SOI) substrate, the substrate comprising: a silicon support layer; a buried oxide (BOX) layer on top of the silicon support layer; and a silicon device layer on top of the BOX layer; a waveguide region, where a portion of the silicon device layer and a portion of the BOX layer underneath the portion of the device layer have been removed, the portion of the BOX layer having been replaced with a layer of silicon and a layer of crystalline oxide on top of the silicon; and a waveguide structure located directly on top of the crystalline oxide layer, the waveguide structure including a P doped region, and an N doped region with an intrinsic region in-between, creating a PIN junction across which a bias can be applied to create a modulation region.

Abstract: A silicon based electro-optically active device and method of producing the same, the device comprising: a silicon-on-insulator (SOI) waveguide; an electro-optically active stack within a cavity of the SOI waveguide, wherein the electro-optically active stack is separated from an insulator layer of the electro-optically active device by a seed layer; and a channel between the electro-optically active stack and the SOI waveguide; wherein the channel is filled with a filling material with a refractive index greater than that of a material forming a sidewall of the cavity to form a bridge-waveguide in the channel between the SOI waveguide and the electro-optically active stack.

Abstract: An optoelectronic device and method of making the same. The device comprising: a substrate; an epitaxial crystalline cladding layer, on top of the substrate; and an optically active region, above the epitaxial crystalline cladding layer; wherein the epitaxial crystalline cladding layer has a refractive index which is less than a refractive index of the optically active region, such that the optical power of the optoelectronic device is confined to the optically active region.

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

Abstract: 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.

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: 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 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 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 method of transfer printing. The method comprising: providing a precursor photonic device, comprising a substrate and a bonding region, wherein the precursor photonic device includes one or more alignment marks located in or adjacent to the bonding region; providing a transfer die, said transfer die including one or more alignment marks; aligning the one or more alignment marks of the precursor photonic device with the one or more alignment marks of the transfer die; and bonding at least a part of the transfer die to the bonding region.

Abstract: A waveguide optoelectronic device comprising a rib waveguide region, and method of manufacturing a rib waveguide region, the rib waveguide region having: a base of a first material, and a ridge extending from the base, at least a portion of the ridge being formed from a chosen semiconductor material which is different from the material of the base wherein the silicon base includes a first slab region at a first side of the ridge and a second slab region at a second side of the ridge; and wherein: a first doped region extends along: the first slab region and along a first sidewall of the ridge, the first sidewall contacting the first slab region; and a second doped region extends along: the second slab region and along a second sidewall of the ridge, the second sidewall contacting the second slab region.

Abstract: A silicon based electro-optically active device and method of producing the same, the device comprising: a silicon-on-insulator (SOI) waveguide; an electro-optically active stack within a cavity of the SOI waveguide, wherein the electro-optically active stack is separated from an insulator layer of the electro-optically active device by a seed layer; and a channel between the electro-optically active stack and the SOI waveguide; wherein the channel is filled with a filling material with a refractive index greater than that of a material forming a sidewall of the cavity to form a bridge-waveguide in the channel between the SOI waveguide and the electro-optically active stack.

Abstract: A silicon based electro-optically active device and method of production thereof. The device comprising: a silicon-on-insulator (SOI) layer; an electro-optically active stack, disposed on top of the SOI layer: a first epitaxially grown structure comprising a first passive waveguide and a second epitaxially grown structure comprising a second passive waveguide, the first and second passive waveguides being disposed adjacent to respective sides of the electro-optically active stack, wherein the first and second passive waveguides are configured to edge couple light from the first passive waveguide into the electro-optically active stack and from the electro-optically active stack into the second passive waveguide; and an evanescent coupling structure, for evanescently coupling light between the SOI layer and the first and second passive waveguides.

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

Abstract: An optoelectronic device and a method of manufacturing the same. The device comprising: a multi-layered optically active stack; an input waveguide, arranged to guide light into the stack; an output waveguide, arranged to guide light out of the stack; and anti-reflective coatings, located between both the input waveguide and the stack and the stack and the output waveguide; wherein the input waveguide and output waveguide are formed of silicon nitride.

Abstract: 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.

Abstract: An optoelectronic device comprising: a silicon-on-insulator (SOI) substrate, the substrate comprising: a silicon support layer; a buried oxide (BOX) layer on top of the silicon support layer; and a silicon device layer on top of the BOX layer; a waveguide region, where a portion of the silicon device layer and a portion of the BOX layer underneath the portion of the device layer have been removed, the portion of the BOX layer having been replaced with a layer of silicon and a layer of crystalline oxide on top of the silicon; and a waveguide structure located directly on top of the crystalline oxide layer, the waveguide structure including a P doped region, and an N doped region with an intrinsic region in-between, creating a PIN junction across which a bias can be applied to create a modulation region.