Abstract: A photonic integrated circuit is provided that may include a substrate; one or more optical sources, on the substrate, to output light associated with a corresponding one or more optical signals; one or more waveguides connected to the one or more optical sources; a multiplexer connected to the one or more waveguides; and one or more light absorptive structures, located on the substrate adjacent to one of the one or more optical sources, one of the one or more waveguides, and/or the multiplexer, to absorb a portion of the light associated with at least one of the corresponding one or more optical signals.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: Consistent with the present disclosure, a photonic integrated circuit (PIC) is provided that has 2 N channels (N being an integer). The PIC is optically coupled to N optical fibers, such that each of N polarization multiplexed optical signals are transmitted over a respective one of the N optical fibers. In another example, each of the N optical fibers supply a respective one of N polarization multiplexed optical signals to the PIC for coherent detection and processing. A multiplexer and demultiplexer may be omitted from the PIC, such that the optical signals are not combined on the PIC. As a result, the transmitted and received optical signals incur less loss and amplified spontaneous emission (ASE) noise. In addition, optical taps may be more readily employed on the PIC to measure outputs of the lasers, such as widely tunable lasers (WTLs), without crossing waveguides.

Abstract: Consistent with the present disclosure, a photonic integrated circuit (PIC) is provided that has 2 N channels (N being an integer). The PIC is optically coupled to N optical fibers, such that each of N polarization multiplexed optical signals are transmitted over a respective one of the N optical fibers. In another example, each of the N optical fibers supply a respective one of N polarization multiplexed optical signals to the PIC for coherent detection and processing. A multiplexer and demultiplexer may be omitted from the PIC, such that the optical signals are not combined on the PIC. As a result, the transmitted and received optical signals incur less loss and amplified spontaneous emission (ASE) noise. In addition, optical taps may be more readily employed on the PIC to measure outputs of the lasers, such as widely tunable lasers (WTLs), without crossing waveguides.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: Consistent with the present disclosure, both arms of an MZ interferometer are “double-folded” and are bent in at least two locations to define first and second acute inner angles. Accordingly, the arms of the MZ interferometer may have substantially the same length, and, further, the MZ interferometer has a more compact geometry. In one example, the arms parallel each other and have a serpentine shape, and, in a further embodiment, the arms parallel one another and have a Z-shape. Accordingly, since the temperature of a PIC upon which the MZ interferometer is provided does not vary significantly over such short distances, the temperatures of both arms is substantially the same.

Abstract: A semiconductor monolithic transmitter photonic integrated circuit (TxPIC) comprises two different situations, either at least one signal channel in the PIC having a modulated source with the channel also extended to include at least one additional element or a plurality of modulated sources comprising N signal channels in the PIC of different transmission wavelengths, where N is equal to or greater than two (2), which may also approximate emission wavelengths along a standardized wavelength grid. In these two different situations, a common active region for such modulated sources and additional channel elements is identified as an extended identical active layer (EIAL), as it extends from a single modulated source to such additional channel elements in the same channel and/or extends to additional modulated sources in separate channels where the number of such channels is N equal to two or greater.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: A photonic integrated circuit is provided that may include a substrate; one or more optical sources, on the substrate, to output light associated with a corresponding one or more optical signals; one or more waveguides connected to the one or more optical sources; a multiplexer connected to the one or more waveguides; and one or more light absorptive structures, located on the substrate adjacent to one of the one or more optical sources, one of the one or more waveguides, and/or the multiplexer, to absorb a portion of the light associated with at least one of the corresponding one or more optical signals.

Abstract: An apparatus having a first waveguide, a second waveguide, a third waveguide, a fourth waveguide, and a fifth waveguide is described. A symmetric coupler has a proximal end and a distal end. The proximal end of the symmetric coupler is coupled to and in optical communication with the first waveguide and the second waveguide. The distal end of the symmetric coupler is coupled to and in optical communication with the fourth waveguide. An asymmetric coupler has a proximal end and a distal end. The asymmetric coupler is in a cascaded configuration with the symmetric coupler. The cascaded configuration has the proximal end of the asymmetric coupler coupled to and in optical communication with the fourth waveguide and the third waveguide. The distal end of the asymmetric coupler is coupled to and in optical communication with the fifth waveguide.

Abstract: A photonic integrated circuit is provided that may include a substrate; one or more optical sources, on the substrate, to output light associated with a corresponding one or more optical signals; one or more waveguides connected to the one or more optical sources; a multiplexer connected to the one or more waveguides; and one or more light absorptive structures, located on the substrate adjacent to one of the one or more optical sources, one of the one or more waveguides, and/or the multiplexer, to absorb a portion of the light associated with at least one of the corresponding one or more optical signals.

Abstract: An apparatus having a first waveguide, a second waveguide, a third waveguide, a fourth waveguide, and a fifth waveguide is described. A symmetric coupler has a proximal end and a distal end. The proximal end of the symmetric coupler is coupled to and in optical communication with the first waveguide and the second waveguide. The distal end of the symmetric coupler is coupled to and in optical communication with the fourth waveguide. An asymmetric coupler has a proximal end and a distal end. The asymmetric coupler is in a cascaded configuration with the symmetric coupler. The cascaded configuration has the proximal end of the asymmetric coupler coupled to and in optical communication with the fourth waveguide and the third waveguide. The distal end of the asymmetric coupler is coupled to and in optical communication with the fifth waveguide.

Abstract: A method provides acceptable performance from a semiconductor transmitter photonic integrated circuit (TxPIC) that contains a plurality of modulated sources each comprising a laser source and an external modulator where each laser source provides a different emission wavelength and each modulated source forms a separate signal channel, comprising the steps of providing at least some of the signal channels with an extended identical active layer (EIAL) so that the modulated sources each have an identical active region wavelength and detuning the laser emission wavelength in each laser source within the EIAL from the laser active region wavelength.

Abstract: An optical modulator includes a splitter, phase modulators, amplitude modulators, intensity modulators, and a combiner. The splitter is configured to receive light, and split the light into portions of the light. Each of the phase modulators is configured to receive a corresponding one of the portions of the light, and modulate a phase of the portion of the light to provide a phase-modulated signal. Each of the amplitude modulators is configured to receive a corresponding one of the phase-modulated signals, and modulate an amplitude of the phase-modulated signal to provide an amplitude-modulated signal. Each of the intensity modulators is configured to receive a corresponding one of the amplitude-modulated signals, and modulate an intensity of the amplitude-modulated signals to provide an intensity-modulated signal. The combiner is configured to receive the intensity-modulated signals, combine the intensity-modulated signals into a combined signal, and output the combined signal.

Abstract: Consistent with the present disclosure, active devices, such as lasers, optical amplifiers, and photodiodes, are integrated on a first substrate, and other optical devices, such as passive devices including polarization rotators and polarization beam combiners, are provided on a second substrate. An array of lenses is provided between the two substrates to provide a low loss optical connection from the first substrate to the second substrate. In addition, the orientation or position of the lenses can be readily controlled with Microelectromechnical System (MEMS) actuators so that the light can be directed precisely to a desired optical element, such as a waveguide. Consistent with a further aspect of the present disclosure, the lenses may be controlled to be misaligned by varying degrees in order to control the amount of light that is supplied from one substrate to another.

Abstract: A device may include a substrate. The device may include a carrier mounted to the substrate. The device may include a transmitter photonic integrated circuit (PIC) mounted on the carrier. The transmitter PIC may include a plurality of lasers that generate an optical signal when a voltage or current is applied to one of the plurality of lasers. The device may include a first microelectromechanical structure (MEMS) mounted to the substrate. The first MEMS may include a first set of lenses. The device may include a planar lightwave circuit (PLC) mounted to the substrate. The PLC may be optically coupled to the plurality of lasers by the first set of lenses of the first MEMS. The device may include a second MEMS, mounted to the substrate, that may include a second set of lenses, which may be configured to optically couple the PLC to an optical fiber.

Abstract: A Raman pump may include a dual output laser configured to output two optical signals; a delay interferometer configured to delay a first of the two optical signals to decorrelate the two optical signals from each other; and a combiner configured to combine the delayed first of the two optical signals and a second of the two optical signals to provide a Raman amplification signal.

Abstract: A device may include a number of optical waveguides, each of which being spaced from one another. The optical waveguides may each include at least one curved section and widths of the curved sections of the optical waveguides may be selected to reduce polarization conversion of light traversing the birefringent optical waveguides.