Abstract: A device may include a plurality of interferometers. The plurality of interferometers may include a parent interferometer, a first child interferometer coupled to a first branch of the parent interferometer, and a second child interferometer coupled to a second branch of the parent interferometer. At least one of the plurality of interferometers may be calibrated by maintaining collinearity of an output of the first branch and the second branch and using perturbation signals.

Abstract: A waveguide coupler includes a first waveguide and a second waveguide. The waveguide coupler also includes a connecting waveguide disposed between the first waveguide and the second waveguide. The connecting waveguide includes a first material having a first index of refraction and a second material having a second index of refraction higher than the first index of refraction.

Abstract: A device may include a plurality of interferometers. The plurality of interferometers may include a parent interferometer, a first child interferometer coupled to a first branch of the parent interferometer, and a second child interferometer coupled to a second branch of the parent interferometer. At least one of the plurality of interferometers may be calibrated by maintaining collinearity of an output of the first branch and the second branch and using perturbation signals.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: A reflective structure includes an input/output port and an optical splitter coupled to the input/output port. The optical splitter has a first branch and a second branch. The reflective structure also includes a first resonant cavity optically coupled to the first branch of the optical splitter. The first resonant cavity comprises a first set of reflectors and a first waveguide region disposed between the first set of reflectors. The reflective structures further includes a second resonant cavity optically coupled to the second branch of the optical splitter. The second resonant cavity comprises a second set of reflectors and a second waveguide region disposed between the second set of reflectors.

Abstract: A reflective structure includes an input/output port and an optical splitter coupled to the input/output port. The optical splitter has a first branch and a second branch. The reflective structure also includes a first resonant cavity optically coupled to the first branch of the optical splitter. The first resonant cavity comprises a first set of reflectors and a first waveguide region disposed between the first set of reflectors. The reflective structures further includes a second resonant cavity optically coupled to the second branch of the optical splitter. The second resonant cavity comprises a second set of reflectors and a second waveguide region disposed between the second set of reflectors.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: A method for fabricating a photonic composite device for splitting functionality across materials comprises providing a composite device having a platform and a chip bonded in the platform. The chip is processed comprising patterning, etching, deposition, and/or other processing steps while the chip is bonded to the platform. The chip is used as a gain medium and the platform is at least partially made of silicon.

Abstract: A composite photonic device comprises a platform, a chip, and a contact layer. The platform comprises silicon. The chip is made of a III-V material. The contact layer has indentations to help control a flow of solder during bonding of the platform with the chip. In some embodiments, pedestals are placed under an optical path to prevent solder from flowing between the chip and the platform at the optical path.

Abstract: A reflective structure includes an input/output port and an optical splitter coupled to the input/output port. The optical splitter has a first branch and a second branch. The reflective structure also includes a first resonant cavity optically coupled to the first branch of the optical splitter. The first resonant cavity comprises a first set of reflectors and a first waveguide region disposed between the first set of reflectors. The reflective structure further includes a second resonant cavity optically coupled to the second branch of the optical splitter. The second resonant cavity comprises a second set of reflectors and a second waveguide region disposed between the second set of reflectors.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: An optical network unit includes a transmit/receive port and a silicon waveguide optically coupled to the transmit/receive port. The optical network unit also includes a tunable filter coupled to the silicon waveguide and providing a first output for a first frequency band and a second output for a second frequency band. The optical network unit further includes a polarization diverse receiver coupled to the tunable filter and a laser coupled to the tunable filter.

Abstract: An optical modulator includes an input port, a first waveguide region comprising silicon and optically coupled to the input port, and a waveguide splitter optically coupled to the first waveguide region and having a first output and a second output. The optical modulator also includes a first phase adjustment section optically coupled to the first output and comprising a first III-V diode and a second phase adjustment section optically coupled to the second output and comprising a second III-V diode. The optical modulator further includes a waveguide coupler optically coupled to the first phase adjustment section and the second phase adjustment section, a second waveguide region comprising silicon and optically coupled to the waveguide coupler, and an output port optically coupled to the second waveguide region.

Abstract: A method for fabricating a composite device comprises providing a platform, providing a chip, and bonding the chip to the platform. The platform has a base layer and a device layer above the base layer. An opening in the device layer exposes a portion of the base layer. The chip is bonded to the portion of the base layer exposed by the opening in the device layer. A portion of the chip extends above the platform and is removed.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: An optical network unit includes a transmit/receive port and a silicon waveguide optically coupled to the transmit/receive port. The optical network unit also includes a tunable filter coupled to the silicon waveguide and providing a first output for a first frequency band and a second output for a second frequency band. The optical network unit further includes a polarization diverse receiver coupled to the tunable filter and a laser coupled to the tunable filter.

Abstract: A composite device for splitting photonic functionality across two or more materials comprises a platform, a chip, and a bond securing the chip to the platform. The platform comprises a base layer and a device layer. The device layer comprises silicon and has an opening exposing a portion of the base layer. The chip, a material, comprises an active region (e.g., gain medium for a laser). The chip is bonded to the portion of the base layer exposed by the opening such that the active region of the chip is aligned with the device layer of the platform. A coating hermetically seals the chip in the platform.

Abstract: A method of operating a BPSK modulator includes receiving an RF signal at the BPSK modulator and splitting the RF signal into a first portion and a second portion that is inverted with respect to the first portion. The method also includes receiving the first portion at a first arm of the BPSK modulator, receiving the second portion at a second arm of the BPSK modulator, applying a first tone to the first arm of the BPSK modulator, and applying a second tone to the second arm of the BPSK modulator. The method further includes measuring a power associated with an output of the BPSK modulator and adjusting a phase applied to at least one of the first arm of the BPSK modulator or the second arm of the BPSK modulator in response to the measured power.

Abstract: A waveguide coupler includes a first waveguide and a second waveguide. The waveguide coupler also includes a connecting waveguide disposed between the first waveguide and the second waveguide. The connecting waveguide includes a first material having a first index of refraction and a second material having a second index of refraction higher than the first index of refraction.