Abstract: A semiconductor laser device is provided. The semiconductor laser device includes: a substrate having a first facet; a guiding layer having a second facet through which an output light is configured to be emitted; a bottom dielectric layer between the substrate and the guiding layer; and a top dielectric layer on the guiding layer. The second facet is at an angle relative to the first facet.

Abstract: A method of fabricating a gain medium includes growing a p-type layer doped with zinc on a substrate, growing an undoped layer including one or both of InP or InGaAsP on the p-type layer, growing a region that includes multiple quantum wells (MQWs) on the undoped layer, and growing an n-type layer on the region. The undoped layer has a thickness that is sufficient to prevent Zn diffusion from the p-type layer into the region during subsequent growth or wafer fabrication steps.

Abstract: A semiconductor laser device is provided. The semiconductor laser device includes: a substrate having a first facet; a guiding layer having a second facet through which an output light is configured to be emitted; a bottom dielectric layer between the substrate and the guiding layer; and a top dielectric layer on the guiding layer. The second facet is at an angle relative to the first facet.

Abstract: A device is provided for optical mode spot size conversion to optically couple a semiconductor waveguide with an optical fiber. The device includes a waveguide comprising a waveguide taper region, which comprises a shoulder portion and a ridge portion above the shoulder portion. The ridge portion has a width that tapers to meet a width of the shoulder portion. The waveguide taper region comprises a first material. The device also has a mode converter coupled to the waveguide. The mode converter includes a plurality of stages, and each of the plurality of stages tapers in a direction similar to a direction of taper of the waveguide taper region. The mode converter is made of a second material different from the first material.

Abstract: A method of fabricating a gain medium includes growing a p-type layer doped with zinc on a substrate, growing an undoped layer including one or both of InP or InGaAsP on the p-type layer, growing a region that includes multiple quantum wells (MQWs) on the undoped layer, and growing an n-type layer on the region. The undoped layer has a thickness that is sufficient to prevent Zn diffusion from the p-type layer into the region during subsequent growth or wafer fabrication steps.

Abstract: A device for optical communication is described. The device comprises two transceivers integrated on one chip. A first transceiver can be used with existing optical-communication architecture. As a more advanced optical-communication architecture becomes adopted, the device can be switched from using the first transceiver to using a second transceiver to communicate using the more advanced optical-communication architecture.

Abstract: A method of fabricating a waveguide mode expander includes providing a substrate including a waveguide, bonding a chiplet including multiple optical material layers in a mounting region adjacent an output end of the waveguide, and selectively removing portions of the chiplet to form tapered stages that successively increase in number and lateral size from a proximal end to a distal end of the chiplet. The first optical material layer supports an input mode substantially the same size as a mode exiting the waveguide. One or more of the overlying layers, when combined with the first layer, support a larger, output optical mode size. Each tapered stage of the mode expander is formed of a portion of a respective layer of the chiplet. The first layer and the tapered stages form a waveguide mode expander that expands an optical mode of light traversing the chiplet.

Abstract: A device is provided for optical mode spot size conversion to optically couple a semiconductor waveguide with an optical fiber. The device includes a waveguide comprising a waveguide taper region, which comprises a shoulder portion and a ridge portion above the shoulder portion. The ridge portion has a width that tapers to meet a width of the shoulder portion. The waveguide taper region comprises a first material. The device also has a mode converter coupled to the waveguide. The mode converter includes a plurality of stages, and each of the plurality of stages tapers in a direction similar to a direction of taper of the waveguide taper region. The mode converter is made of a second material different from the first material.

Abstract: A method of fabricating a gain medium includes growing a p-type layer doped with zinc on a substrate, growing an undoped layer including one or both of InP or InGaAsP on the p-type layer, growing a region that includes multiple quantum wells (MQWs) on the undoped layer, and growing an n-type layer on the region. The undoped layer has a thickness that is sufficient to prevent Zn diffusion from the p-type layer into the region during subsequent growth or wafer fabrication steps.

Abstract: A method of fabricating a gain medium includes growing a p-type layer doped with zinc on a substrate, growing an undoped layer including one or both of InP or InGaAsP on the p-type layer, growing a region that includes multiple quantum wells (MQWs) on the undoped layer, and growing an n-type layer on the region. The undoped layer has a thickness that is sufficient to prevent Zn diffusion from the p-type layer into the region during subsequent growth or wafer fabrication steps.

Abstract: A device is provided for optical mode spot size conversion to optically couple a semiconductor waveguide with an optical fiber. The device includes a waveguide comprising a waveguide taper region, which comprises a shoulder portion and a ridge portion above the shoulder portion. The ridge portion has a width that tapers to meet a width of the shoulder portion. The waveguide taper region comprises a first material. The device also has a mode converter coupled to the waveguide. The mode converter includes a plurality of stages, and each of the plurality of stages tapers in a direction similar to a direction of taper of the waveguide taper region. The mode converter is made of a second material different from the first material.

Abstract: A v-groove assembly is used to edge couple a lensed fiber (e.g., an optical fiber made of silica) with a waveguide in a photonic chip. The v-groove assembly is made from fused silica. Fused silica is used to so that an adhesive (e.g., epoxy resin) used in bonding the lensed fiber to the v-groove assembly and/or bonding the v-groove assembly to the photonic chip can be cured, at least partially, by light.

Abstract: A device is provided for optical mode spot size conversion to optically couple a semiconductor waveguide with an optical fiber. The device includes a waveguide comprising a waveguide taper region, which comprises a shoulder portion and a ridge portion above the shoulder portion. The ridge portion has a width that tapers to meet a width of the shoulder portion. The waveguide taper region comprises a first material. The device also has a mode converter coupled to the waveguide. The mode converter includes a plurality of stages, and each of the plurality of stages tapers in a direction similar to a direction of taper of the waveguide taper region. The mode converter is made of a second material different from the first material.

Abstract: A device for optical communication is described. The device comprises two transceivers integrated on one chip. A first transceiver can be used with existing optical-communication architecture. As a more advanced optical-communication architecture becomes adopted, the device can be switched from using the first transceiver to using a second transceiver to communicate using the more advanced optical-communication architecture.

Abstract: A method of fabricating a waveguide mode expander includes providing a substrate including a waveguide, bonding a chiplet including multiple optical material layers in a mounting region adjacent an output end of the waveguide, and selectively removing portions of the chiplet to form tapered stages that successively increase in number and lateral size from a proximal end to a distal end of the chiplet. The first optical material layer supports an input mode substantially the same size as a mode exiting the waveguide. One or more of the overlying layers, when combined with the first layer, support a larger, output optical mode size. Each tapered stage of the mode expander is formed of a portion of a respective layer of the chiplet. The first layer and the tapered stages form a waveguide mode expander that expands an optical mode of light traversing the chiplet.

Abstract: A v-groove assembly is used to edge couple a lensed fiber (e.g., an optical fiber made of silica) with a waveguide in a photonic chip. The v-groove assembly is made from fused silica. Fused silica is used to so that an adhesive (e.g., epoxy resin) used in bonding the lensed fiber to the v-groove assembly and/or bonding the v-groove assembly to the photonic chip can be cured, at least partially, by light.

Abstract: A method of fabricating a waveguide mode expander includes providing a substrate including a waveguide, bonding a chiplet including multiple optical material layers in a mounting region adjacent an output end of the waveguide, and selectively removing portions of the chiplet to form tapered stages that successively increase in number and lateral size from a proximal end to a distal end of the chiplet. The first optical material layer supports an input mode substantially the same size as a mode exiting the waveguide. One or more of the overlying layers, when combined with the first layer, support a larger, output optical mode size. Each tapered stage of the mode expander is formed of a portion of a respective layer of the chiplet. The first layer and the tapered stages form a waveguide mode expander that expands an optical mode of light traversing the chiplet.

Abstract: A waveguide mode expander couples a smaller optical mode in a semiconductor waveguide to a larger optical mode in an optical fiber. The waveguide mode expander comprises a shoulder made of crystalline silicon and a ridge made of non-crystalline silicon (e.g., amorphous silicon). In some embodiments, the ridge of the waveguide mode expander has a plurality of stages, the plurality of stages have different widths and/or thicknesses at a given cross section.

Abstract: A v-groove assembly is used to edge couple a lensed fiber (e.g., an optical fiber made of silica) with a waveguide in a photonic chip. The v-groove assembly is made from fused silica. Fused silica is used to so that an adhesive (e.g., epoxy resin) used in bonding the lensed fiber to the v-groove assembly and/or bonding the v-groove assembly to the photonic chip can be cured, at least partially, by light.

Abstract: A multi-channel transceiver using a floating frequency grid for multi-channel, optical communication is presented. Transmitter frequencies are permitted to drift, and a receiver is tuned to compensate for drifts in the transmitter frequencies.