Abstract: The present disclosure is directed to light-distribution systems on photonic integrated circuits (PIC) that split and amplify a light signal received from at least one remotely located laser into a plurality of amplified light signals, where amplification is provided by an integrated semiconductor optical amplifier (SOA). By locating the laser remotely with respect to the SOA-based PIC, the laser and PIC can be subjected to different ambient environmental conditions. Additionally, a lower-power laser can be used since the optical loss associated with splitting is compensated for by the amplification. As a result, lower current densities and optical powers can be used in both the source laser and the SOA. In some embodiments, the sequence of power splitting and amplification is repeated multiple times, thereby enabling system to scale gracefully.

Abstract: The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it.

Abstract: The present disclosure is directed to light-distribution systems on photonic integrated circuits (PIC) that split and amplify a light signal received from at least one remotely located laser into a plurality of amplified light signals, where amplification is provided by an integrated semiconductor optical amplifier (SOA). By locating the laser remotely with respect to the SOA-based PIC, the laser and PIC can be subjected to different ambient environmental conditions. Additionally, a lower-power laser can be used since the optical loss associated with splitting is compensated for by the amplification. As a result, lower current densities and optical powers can be used in both the source laser and the SOA. In some embodiments, the sequence of power splitting and amplification is repeated multiple times, thereby enabling system to scale gracefully.

Abstract: The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it.

Abstract: In accordance with a method, forming a semiconductor laser with a photonic integrated circuit (PIC) a laser die is provided that includes a semiconductor laser and a silicon-based photonic waveguide disposed on a silicon substrate. The silicon-based photonic waveguide is configured to receive optical energy generated by the semiconductor laser and provide the optical energy as output energy that is output from the laser die. The laser die is coupled with the PIC so that the optical energy output from the laser die is coupled to a photonic waveguide located on the PIC.

Abstract: A circuit comprising: first and second transistors connected in series; a third transistor (TT) comprising a source connected to a source of the second transistor (ST), a gate connected to a gate of ST, and a drain connected to a gate of the first transistor (FT); and a gate driver circuit connected to the gates of FT, ST and TT and configured to provide (i) a first drive signal to the gate of FT to cause FT to transition between an on state and an off state and (ii) a second drive signal to the gates of ST and TT to cause ST and TT to transition between on states and off states. The TT is configured to prevent a shoot-through condition in the circuit by pulling the first drive signal down to a level of the source of the ST when the ST is in the on state.

Abstract: A circuit comprising: first and second transistors connected in series; a third transistor (TT) comprising a source connected to a source of the second transistor (ST), a gate connected to a gate of ST, and a drain connected to a gate of the first transistor (FT); and a gate driver circuit connected to the gates of FT, ST and TT and configured to provide (i) a first drive signal to the gate of FT to cause FT to transition between an on state and an off state and (ii) a second drive signal to the gates of ST and TT to cause ST and TT to transition between on states and off states. The TT is configured to prevent a shoot-through condition in the circuit by pulling the first drive signal down to a level of the source of the ST when the ST is in the on state.

Abstract: Integrated-optics systems are presented in which an optically active device is optically coupled with a silicon waveguide via a passive compound-semiconductor waveguide. In a first region, the passive waveguide and the optically active device collectively define a composite waveguide structure, where the optically active device functions as the central ridge portion of a rib-waveguide structure. The optically active device is configured to control the vertical position of an optical mode in the composite waveguide along its length such that the optical mode is optically coupled into the passive waveguide with low loss. The passive waveguide and the silicon waveguide collectively define a vertical coupler in a second region, where the passive and silicon waveguides are configured to control the distribution of the optical mode along the length of the coupler, thereby enabling the entire mode to transition between the passive and silicon waveguides with low loss.

Abstract: The present Specification is directed to the heterogeneous integration of compound-semiconductor devices on indirect-bandgap material substrates. A chip comprising compound-semiconductor layer stack disposed on a handle substrate of germanium is bonded, stack-side down, to a silicon layer disposed on a host substrate. The use of a germanium handle substrate enables the handle substrate to be removed after bonding using methods that are highly selective for germanium over the compound semiconductor layer stack. As a result, the compound-semiconductor layer stack does not need to be protected during handle substrate removal and the handle substrate can be completely removed without causing damage to the compound-semiconductor layer stack. As a result, after handle-substrate removal, the materials of the layer stack can be processed further to define one or more optically active devices in conventional fashion.

Abstract: The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it.

Abstract: The present disclosure is directed toward architectures that combine DWDM and CWDM concepts in a single PIC. Transmitter stages in accordance with the present disclosure include a plurality of multiwavelength lasers having regions of separately grown epitaxial material whose gain peaks are centered at different wavelengths. Each laser launches a wavelength comb comprising a plurality of wavelength signals into a PLC, where the wavelengths within each wavelength comb are separated by a wavelength spacing that is smaller than that between adjacent wavelength combs. In some embodiments, the PLC includes modulator banks for encoding data on the wavelength signals and combining them to produce a composite DWDM output signal. In some embodiments, a receiver stage is included for demultiplexing a composite DWDM input signal and detecting each wavelength channel within it.

Abstract: Integrated-optics systems are presented in which an active-material stack is disposed on a coupling layer in a first region to collectively define an OA waveguide that supports an optical mode of a light signal. The coupling layer is patterned to define a coupling waveguide and a passive waveguide, which are formed as two abutting, optically coupled segments of the coupling layer. The lateral dimensions of the active-material stack are configured to control the shape and vertical position of the optical mode at any location along the length of the OA waveguide. The active-material stack includes a taper that narrows along its length such that the optical mode is located completely in the coupling waveguide where the coupling waveguide abuts the passive waveguide. In some embodiments, the passive layer is optically coupled with the OA waveguide and a silicon waveguide, thereby enabling light to propagate between them.

Abstract: Integrated-optics systems are presented in which an optically active device is optically coupled with a silicon waveguide via a passive compound-semiconductor waveguide. In a first region, the passive waveguide and the optically active device collectively define a composite waveguide structure, where the optically active device functions as the central ridge portion of a rib-waveguide structure. The optically active device is configured to control the vertical position of an optical mode in the composite waveguide along its length such that the optical mode is optically coupled into the passive waveguide with low loss. The passive waveguide and the silicon waveguide collectively define a vertical coupler in a second region, where the passive and silicon waveguides are configured to control the distribution of the optical mode along the length of the coupler, thereby enabling the entire mode to transition between the passive and silicon waveguides with low loss.

Abstract: Integrated-optics systems are presented in which an optically active device is optically coupled with a silicon waveguide via a passive compound-semiconductor waveguide. In a first region, the passive waveguide and the optically active device collectively define a composite waveguide structure, where the optically active device functions as the central ridge portion of a rib-waveguide structure. The optically active device is configured to control the vertical position of an optical mode in the composite waveguide along its length such that the optical mode is optically coupled into the passive waveguide with low loss. The passive waveguide and the silicon waveguide collectively define a vertical coupler in a second region, where the passive and silicon waveguides are configured to control the distribution of the optical mode along the length of the coupler, thereby enabling the entire mode to transition between the passive and silicon waveguides with low loss.

Abstract: The present disclosure is directed to light-distribution systems on photonic integrated circuits (PIC) that split and amplify a light signal received from at least one remotely located laser into a plurality of amplified light signals, where amplification is provided by an integrated semiconductor optical amplifier (SOA). By locating the laser remotely with respect to the SOA-based PIC, the laser and PIC can be subjected to different ambient environmental conditions. Additionally, a lower-power laser can be used since the optical loss associated with splitting is compensated for by the amplification. As a result, lower current densities and optical powers can be used in both the source laser and the SOA. In some embodiments, the sequence of power splitting and amplification is repeated multiple times, thereby enabling system to scale gracefully.

Abstract: Aspects of the present disclosure are directed to wavelength division multiplexing systems comprising arrays of spectrally selective devices that are arranged on a substrate to compensate for perturbations of the spectral characteristics of the devices due to factors such as temperature non-uniformity, inherent spectral non-uniformity, and the like. As a result, shifts in the center wavelengths and/or changes in the wavelength spacing for the wavelength channels of a WDM system due to such perturbations are mitigated. In some embodiments, an array of spectrally selective devices is arranged on a substrate such that their respective wavelength channels are not linearly correlated with their physical position within the array, enabling the devices to be arranged in pairs that are subject to substantially the same environmental conditions and/or operate on nearly the same spectral range.

Abstract: Integrated-optics systems are presented in which an optically active device is optically coupled with a silicon waveguide via a passive compound-semiconductor waveguide. In a first region, the passive waveguide and the optically active device collectively define a composite waveguide structure, where the optically active device functions as the central ridge portion of a rib-waveguide structure. The optically active device is configured to control the vertical position of an optical mode in the composite waveguide along its length such that the optical mode is optically coupled into the passive waveguide with low loss. The passive waveguide and the silicon waveguide collectively define a vertical coupler in a second region, where the passive and silicon waveguides are configured to control the distribution of the optical mode along the length of the coupler, thereby enabling the entire mode to transition between the passive and silicon waveguides with low loss.

Abstract: Integrated-optics systems are presented in which an active-material stack is disposed on a coupling layer in a first region to collectively define an OA waveguide that supports an optical mode of a light signal. The coupling layer is patterned to define a coupling waveguide and a passive waveguide, which are formed as two abutting, optically coupled segments of the coupling layer. The lateral dimensions of the active-material stack are configured to control the shape and vertical position of the optical mode at any location along the length of the OA waveguide. The active-material stack includes a taper that narrows along its length such that the optical mode is located completely in the coupling waveguide where the coupling waveguide abuts the passive waveguide. In some embodiments, the passive layer is optically coupled with the OA waveguide and a silicon waveguide, thereby enabling light to propagate between them.

Abstract: Aspects of the present disclosure are directed to wavelength division multiplexing systems comprising arrays of spectrally selective devices that are arranged on a substrate to compensate for perturbations of the spectral characteristics of the devices due to factors such as temperature non-uniformity, inherent spectral non-uniformity, and the like. As a result, shifts in the center wavelengths and/or changes in the wavelength spacing for the wavelength channels of a WDM system due to such perturbations are mitigated. In some embodiments, an array of spectrally selective devices is arranged on a substrate such that their respective wavelength channels are not linearly correlated with their physical position within the array, enabling the devices to be arranged in pairs that are subject to substantially the same environmental conditions and/or operate on nearly the same spectral range.

Abstract: Integrated-optics systems are presented in which an active-material stack is disposed on a coupling layer in a first region to collectively define an OA waveguide that supports an optical mode of a light signal. The coupling layer is patterned to define a coupling waveguide and a passive waveguide, which are formed as two abutting, optically coupled segments of the coupling layer. The lateral dimensions of the active-material stack are configured to control the shape and vertical position of the optical mode at any location along the length of the OA waveguide. The active-material stack includes a taper that narrows along its length such that the optical mode is located completely in the coupling waveguide where the coupling waveguide abuts the passive waveguide. In some embodiments, the passive layer is optically coupled with the OA waveguide and a silicon waveguide, thereby enabling light to propagate between them.