A photonics frequency comb generator includes two integrated dies: an indium phosphide die laser of a first wavelength is grown on from, and a silicon photonics die having a microring resonator connected to the laser and frequency modulators. The microring resonator converts the first wavelength into a number of second wavelengths. One type of the microring resonator is a hybrid non-linear optical wavelength generator, comprising non-silicon materials, such as SiC or SiGe built on silicon to yield a non-linear wavelength generation. The second wavelengths are generated by adjusting the ring's geometric size and a distance between the ring and the traverse waveguide. Another type of microring resonator splits the first wavelength into a plurality of second wavelengths and transmits the multiple second wavelengths to filters and modulators, and each selects and modulates one of the second wavelengths in a one-to-one relationship. This frequency comb generator has applications in WDM/CWDM and multi-chip modules in high speed transceivers.

A method and system for locking the resonance frequency of ring resonators by using laser sources to emit a plurality of different wavelengths, applying a tagging signal to each of the wavelengths, multiplexing the tagged wavelengths using a wavelength division multiplexor, coupling the multiplexed tagged wavelengths onto a bus waveguide, detecting the multiplexed tagged wavelengths with a first photodetector disposed before a first ring resonator and a second photodetector disposed after a last ring resonator of a plurality of ring resonators, sending the signals detected by the first and second photodetector to a processor, which identifies and processes the tagging signals, generating a control signal for each ring resonator, by the processor and applying the control signals to phase shifters on each ring resonator of the plurality of ring resonators to tune and align the resonance wavelengths of the ring resonators with the wavelengths of the corresponding laser sources.

Integrated optical filter and photodetectors and methods of fabrication thereof are described herein according to the present disclosure. An example of an integrated optical filter and photodetector described herein includes a substrate, an insulator layer on the substrate, and a semiconductor layer on the insulator layer. An optical filter having a resonant cavity is formed in or on the semiconductor layer. The integrated optical filter and photodetector further includes two first metal fingers and a second metal finger interdigitated between the two first metal fingers on the semiconductor layer forming Schottky barriers. The first metal fingers are constructed from a different metal relative to the second metal finger.

The nonlinearities of cascaded and series configurations of Mach-Zehnder electrooptic modulators are utilized to increase signal bandwidth and boost signal fidelity in electronic digital to analog converters.

Consistent with the present disclosure, a local oscillator is provided in a receiver. The local oscillator laser a first and second mirrors and phase section and heaters are provided adjacent each portion of the laser, such that the temperature and thus the frequency of light output from the local oscillator laser may be tuned. Applying electrical power, such as a current or voltage to the phase section may result in rapid frequency tuning of light output from the local oscillator laser but over a limited frequency range. Temperature changes to the mirror sections, however, may afford frequency tuning over a wider range, but frequency tuning the mirror sections requires more time than that required to tune the phase section. Consistent with the present disclosure, a tuning method and apparatus is provided that optimizes laser tuning by selectively tuning the phase and mirror sections.

Systems and methods for increasing throughput of a photonic processor by using photonic degrees of freedom (DOF) are provided. The photonic processor includes a multiplexer configured to multiplex, using at least one photonic DOF, multiple encoded optical signals into a multiplexed optical signal. The photonic processor also includes a detector coupled to an output of an optical path including the multiplexer, the detector being configured to generate a first current based on the multiplexed optical signal or a demultiplexed portion of the multiplexed optical signal. The photonic processor further includes a modulator coupled to and output of the detector, the modulator being configured to generate a second current by modulating the first current.

A photonics frequency comb generator includes two integrated dies: an indium phosphide die laser of a first wavelength is grown on from, and a silicon photonics die having a microring resonator connected to the laser and frequency modulators. The microring resonator converts the first wavelength into a number of second wavelengths. One type of the microring resonator is a hybrid non-linear optical wavelength generator, comprising non-silicon materials, such as SiC or SiGe built on silicon to yield a non-linear wavelength generation. The second wavelengths are generated by adjusting the ring's geometric size and a distance between the ring and the traverse waveguide. Another type of microring resonator splits the first wavelength into a plurality of second wavelengths and transmits the multiple second wavelengths to filters and modulators, and each selects and modulates one of the second wavelengths in a one-to-one relationship. This frequency comb generator has applications in WDM/CWDM and multi-chip modules in high speed transceivers.

An active optical modulator receives a radio frequency signal and provides an intensity modulated optical signal. The optical modulator is formed on a substrate having a doped region. An interferometer is formed on the substrate having a first path and a second path. A low noise amplifier receives the radio frequency signal and provides an electrical field to the paths. A signal laser provides an optical signal to the interferometer which is modulated and interfered to produce an intensity modulated optical signal. A pump laser provides an optical gain signal to the interferometer where it adds gain to the optical signal in the interferometer by interaction with the doped region of the substrate.

A coherent optical transmitter includes circuitry connected to a coherent modulator; and a plurality of tunable optical filters (TOFs) connected to one another and connected to an output of the coherent modulator, wherein the plurality of tunable optical filters are configurable to create an effective transfer function having a variable width. The TOFs are cascaded and can be included in discrete form on electro-optic printed circuit boards (PCBs), or integrated in various electro-optic material systems such as in silicon photonics, photonic integrated circuits (PICs), as well as hybrid and other approaches. The advantage of this approach includes improved OSNR in colorless transmitters.

An optical module switch device includes a first serial-parallel-converter coupled to first signal-lines coupled to optical modules, and second signal-lines, a number of the second signal-lines being greater than the first signal-lines thereof, and configured to transmit/receive first signals at a first transmission-rate to/from the optical modules by using the first signal-lines, respectively, a second serial-parallel-converter coupled to second signal-lines coupled to the first serial-parallel-converter, and third signal-lines, a number of the third lines being greater than the second signal-lines thereof, and configured to transmit/receive second signals at a second transmission-rate lower than the first transmission-rate to/from the first serial-parallel-converter by using the second signal-lines, respectively, and a switch circuit coupled to the third signal-lines, and configured to transmit/receive third signals at a third transmission-rate lower than the second transmission-rate to/from the second serial-parallel-converter by using the third signal-lines, respectively, to perform routing processing based on the received third signals.