Abstract: An optical circuit is used with continuous wave signals having different wavelengths at a channel spacing from one another. A portion of the optical circuit is implemented in a photonic integrated circuit. Modulators in a modulation stage modulate the continuous wave signals to produce modulated signals. A multiplexing stage, which can have multiplexing filters, power combiners, or power couplers, multiplexes the continuous wave or modulated signals to produce multiplexed signals. The multiplexing stage may be placed either before or after the modulation stage. One or more polarization rotator and combiner (PRC) devices in a final stage combines the multiplexed signals into an output signal. The output signal has a first set of the different wavelengths at a first polarization and has a second separate set of the different wavelengths at a second polarization orthogonal to the first polarization.

Abstract: An optical waveguide interferometer may include an input section, a middle section, and an output section, where the optical waveguide interferometer further includes a first arm portion having a first length that spans the input section, the middle section, and the output section, and a second arm portion having a second length that spans the input section, the middle section, and the output section, where the first length of the first arm portion is less than the second length of the second arm portion, and where the second arm portion has a curved shape.

Abstract: An optoelectronic circuit used with signal light comprises photonic. The photonic devices are configured to condition the signal light and are fabricated with an optical characteristic being electronically tunable. A fabricated performance of the optical characteristic can be varied from a target performance due to a difference (e.g., alteration, change, error, or discrepancy) in the process used to fabricate the device. A ground bus, a power bus, and banks of electronic components are disposed on the platform in electrical communication with the photonic devices. The electronic components in a given bank are selectively configurable to tune the optical characteristic of the associated device so a variance can be diminished between the fabrication and target performances of the device's optical characteristic due to the difference in the fabrication process.

Abstract: An optical circuit is used with continuous wave signals having different wavelengths at a channel spacing from one another. A portion of the optical circuit is implemented in a photonic integrated circuit. Modulators in a modulation stage modulate the continuous wave signals to produce modulated signals. A multiplexing stage, which can have multiplexing filters, power combiners, or power couplers, multiplexes the continuous wave or modulated signals to produce multiplexed signals. The multiplexing stage may be placed either before or after the modulation stage. One or more polarization rotator and combiner (PRC) devices in a final stage combines the multiplexed signals into an output signal. The output signal has a first set of the different wavelengths at a first polarization and has a second separate set of the different wavelengths at a second polarization orthogonal to the first polarization.

Abstract: An optoelectronic circuit used with signal light comprises photonic devices disposed on a platform. The photonic devices are configured to condition the signal light and are fabricated with an optical characteristic being electronically tunable. A fabricated performance of the optical characteristic can be varied from a target performance due to a difference (e.g., alteration, change, error, or discrepancy) in the process used to fabricate the device. A ground bus, a power bus, and banks of electronic components are disposed on the platform in electrical communication with the photonic devices. The electronic components in a given bank are selectively configurable to tune the optical characteristic of the associated device so a variance can be diminished between the fabrication and target performances of the device's optical characteristic due to the difference in the fabrication process.

Abstract: An optical frequency-division demultiplexer, with a plurality of cascaded half-band filters, each of which comprises a plurality of stages. At least a first half-band filter and a second half-band filter have different orders but the same channel spacing.

Abstract: A photonic integrated circuit (PIC) device has photonic devices arranged in an array with respect to control and common conductors. Each of the photonic devices has a photonic component (e.g., photodiode, thermo-optic phase shifter, etc.) and a switching diode connected in series with one another between a control connection and a common connection. The photonic component has at least one optical port, which can be coupled to a waveguide in the PIC device. The switching diode is configured to switch between reverse and forward bias in response to the electrical signals. In this way, control circuitry for providing control and monitoring signals to the conductors can be greatly simplified, and the PIC device can be more compact.

Abstract: A photonics integrated circuit chip includes a substrate, an interface port unit IPU formed on the substrate, a photonics circuit unit PCU formed on the substrate, a photonics circuit 1PC formed on the substrate and optically coupled between the interface port unit IPU and the photonics circuit unit PCU, and a photonics circuit 2PC formed on the substrate and optically coupled between the interface port unit IPU and the photonics circuit unit PCU in parallel with photonics circuit 1PC. The photonics circuit 1PC and the photonics circuit 2PC may be at least one of the following: functional duplicates of each other with intentionally introduced physical differences in their fabrication layouts; differently optically tuned versions of each other; and/or functionally equivalent versions of each other with intentionally introduced differences in their circuit layouts.

Abstract: A photonic integrated circuit (PIC) device has photonic devices arranged in an array with respect to control and common conductors. Each of the photonic devices has a photonic component (e.g., photodiode, thermo-optic phase shifter, etc.) and a switching diode connected in series with one another between a control connection and a common connection. The photonic component has at least one optical port, which can be coupled to a waveguide in the PIC device. The switching diode is configured to switch between reverse and forward bias in response to the electrical signals. In this way, control circuitry for providing control and monitoring signals to the conductors can be greatly simplified, and the PIC device can be more compact.

Abstract: An apparatus including an optical modulator and an electronic controller. The optical modulator includes a parallel-nested pair of MZIs, each arm of the MZIs including one or more EAMs therein. The electronic controller is electrically connected to drive the MZIs such that the optical modulator outputs an optical carrier modulated according to a quadrature amplitude modulation constellation with at least five different symbols.

Abstract: An optoelectronic circuit used with signal light comprises photonic devices disposed on a platform. The photonic devices are configured to condition the signal light and are fabricated with an optical characteristic being electronically tunable. A fabricated performance of the optical characteristic can be varied from a target performance due to a difference (e.g., alteration, change, error, or discrepancy) in the process used to fabricate the device. A ground bus, a power bus, and banks of electronic components are disposed on the platform in electrical communication with the photonic devices. The electronic components in a given bank are selectively configurable to tune the optical characteristic of the associated device so a variance can be diminished between the fabrication and target performances of the device's optical characteristic due to the difference in the fabrication process.

Abstract: An optical circuit is used with continuous wave signals having different wavelengths at a channel spacing from one another. A portion of the optical circuit is implemented in a photonic integrated circuit. Modulators in a modulation stage modulate the continuous wave signals to produce modulated signals. A multiplexing stage, which can have multiplexing filters, power combiners, or power couplers, multiplexes the continuous wave or modulated signals to produce multiplexed signals. The multiplexing stage may be placed either before or after the modulation stage. One or more polarization rotator and combiner (PRC) devices in a final stage combines the multiplexed signals into an output signal. The output signal has a first set of the different wavelengths at a first polarization and has a second separate set of the different wavelengths at a second polarization orthogonal to the first polarization.

Abstract: A photonic integrated circuit (PIC) device has photonic devices arranged in an array with respect to control and common conductors. Each of the photonic devices has a photonic component (e.g., photodiode, thermo-optic phase shifter, etc.) and a switching diode connected in series with one another between a control connection and a common connection. The photonic component has at least one optical port, which can be coupled to a waveguide in the PIC device. The switching diode is configured to switch between reverse and forward bias in response to the electrical signals. In this way, control circuitry for providing control and monitoring signals to the conductors can be greatly simplified, and the PIC device can be more compact.

Abstract: An apparatus including a carrier mount having a staircase of steps in an opening in the carrier mount and a plurality of dies, each one of the dies having at least a portion of an edge of a major surface thereof located on one of the steps corresponding to the one of the dies such that the dies form a stack, major surfaces of the dies being substantially parallel in the stack, each of the dies having one or more electro-optical devices thereon.

Abstract: An apparatus including a carrier mount having a staircase of steps in an opening in the carrier mount and a plurality of dies, each one of the dies having at least a portion of an edge of a major surface thereof located on one of the steps corresponding to the one of the dies such that the dies form a stack, major surfaces of the dies being substantially parallel in the stack, each of the dies having one or more electro-optical devices thereon.

Abstract: An optical system having a plurality of ring resonators that can be tuned by regulating their local temperatures in a manner that enables: initial spectral alignment of the optical resonances with the desired carrier wavelengths; fine-tuning of the ring resonators to spectrally align a selected feature of the optical resonances with the carrier wavelengths; and continuous tuning of the ring resonators to counter any detuning thereof during operation. The initial spectral alignment can be performed using intensity/frequency modulation of different carrier wavelengths with different respective frequencies and detection of said frequencies in the photocurrents generated by the individual ring resonators under reverse-bias conditions.

Abstract: An optical device that can be used as an optical hybrid, e.g., in CMOS-compatible PICs. In an example embodiment, the optical device has a single optical input and four optical outputs. The two optical input signals to be mixed in the optical device are applied to the single optical input as transverse electric (TE) and transverse magnetic (TM) polarization components, respectively, of the corresponding polarization-multiplexed optical input signal. In response to the latter, the optical device causes the four outputs to receive four different relative-phase combinations of the two optical input signals, each combination being coupled into a TE waveguide mode at the respective optical output. A PIC having one or more instances of the optical device can be used, e.g., to implement a coherent optical receiver, wherein the TE and TM polarization components of the optical input signal are populated by a communication signal and a local-oscillator signal.

Abstract: An apparatus including an optical modulator and an electronic controller. The optical modulator includes a parallel-nested pair of MZIs, each arm of the MZIs including one or more EAMs therein. The electronic controller is electrically connected to drive the MZIs such that the optical modulator outputs an optical carrier modulated according to a quadrature amplitude modulation constellation with at least five different symbols.

Abstract: An apparatus including an external cavity laser with an optical cavity, the optical cavity bounded by optical reflectors. The optical cavity can include an optical gain module capable of amplifying light, a tunable endless optical phase shifter and a wavelength-tunable optical filter. The apparatus can also include an electronic control module connected to enable adjustment of a phase shift accumulated by the light propagating through the tunable endless optical phase shifter and connected to enable adjustment of a passband wavelength of the wavelength tunable optical filter. Another apparatus as described above with no wavelength-tunable optical filter present.

Abstract: An apparatus including first, second, third and fourth photodiodes, optical mixer and first and second optical power splitters. The optical mixer has two or more input ports, three output ports to output first, second and third mixtures of light corresponding to input light received from the input ports and transferred to the output ports. The first splitter has an input port and first and second output ports, to transmit part of one of the mixtures of light from one of the output ports to the first photodiode and a remaining part of the one mixture of light from the other one of the output ports to the third photodiode. The second splitter has an input port and first and second output ports, the second splitter to transmit part of another one of the mixtures of light from one of the output ports to the first photodiode and a remaining part of the other one of the mixtures of light from the other one of the output ports to the fourth photodiode.