Abstract:
A transceiver includes an optical waveguide and a first filter optically coupled to the optical waveguide and operable to filter a first optical signal in a first wavelength band propagating downstream. A center wavelength of the first wavelength band is tunable. The transceiver also includes a first receiver optically coupled to the first filter and a second filter optically coupled to the optical waveguide and operable to filter a second optical signal in a second wavelength band propagating downstream. The second wavelength band is different from the first wavelength band. The transceiver further includes a second receiver optically coupled to the second filter to receive the second optical signal and a laser optically coupled to the optical waveguide and operable to output radiation in a third wavelength band propagating upstream. The third wavelength band is different from both the first wavelength band and the second wavelength band.
Abstract:
A method of fabricating a composite semiconductor structure includes providing an SOI substrate including a plurality of silicon-based devices and providing a compound semiconductor substrate including a plurality of photonic devices. The method also includes dicing the compound semiconductor substrate to provide a plurality of photonic dies. Each die includes one or more of the plurality of photonics devices. The method further includes providing an assembly substrate, mounting the plurality of photonic dies on predetermined portions of the assembly substrate, aligning the SOI substrate and the assembly substrate, joining the SOI substrate and the assembly substrate to form a composite substrate structure, and removing at least a portion of the assembly substrate from the composite substrate structure.
Abstract:
A semiconductor laser has a mirror formed in a gain chip. The mirror can be placed in the gain chip to provide a broadband reflector to support multiple lasers using the gain chip. The mirror can also be placed in the gain chip to have the semiconductor laser be more efficient or more powerful by changing an optical path length of the gain of the semiconductor laser.
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 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 III-V 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 hermitically seals the chip in the platform.
Abstract:
A photonics system includes a transmit photonics module and a receive photonics module. The photonics system also includes a transmit waveguide coupled to the transmit photonics module, a first optical switch integrated with the transmit waveguide, and a diagnostics waveguide optically coupled to the first optical switch. The photonics system further includes a receive waveguide coupled to the receive photonics module and a second optical switch integrated with the receive waveguide and optically coupled to the diagnostics waveguide.
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 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 of fabricating a composite semiconductor structure includes providing a first substrate comprising a first material and having a first surface and forming a plurality of pedestals extending to a predetermined height in a direction normal to the first surface. The method also includes attaching a plurality of elements comprising a second material to each of the plurality of pedestals, providing a second substrate having one or more structures disposed thereon, and aligning the first substrate and the second substrate. The method further includes joining the first substrate and the second substrate to form the composite substrate structure and removing at least a portion of the first substrate from the composite substrate structure.
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.