Hewlett Packard Enterprise Development LP

Geza Kurczveil

Raymond G Beausoleil

Di Liang

Marco Fiorentino

Zhihong Huang

Mir Ashkan Seyedi

Chong Zhang

Stanley Cheung

Yuan Yuan

Xiaoge Zeng

Sudharsanan Srinivasan

Kevin B Leigh

Paul Kessler Rosenberg

Ashkan Seyedi

Chih C Shih

Yiwei Peng

David Kielpinski

Bassem Tossoun

Xian Xiao

Jared Hulme

Antoine Deseos

One aspect can provide a method for fabricating a photonic integrated circuit (PIC) with an embedded optical power monitor. The method can include creating a photomask based on a design of the PIC, the photomask comprising a pattern defining an optical waveguide for embedding the optical power monitor. Creating the photomask can include introducing a predetermined level of roughness along at least one edge of the pattern defining the optical waveguide. The method can further include fabricating the PIC, which can include using the photomask to create the optical waveguide with the introduced roughness on a sidewall corresponding to the edge of the pattern, thereby allowing light absorbed by the roughness to create free carriers for detection by the optical power monitor.

Hitless optical power monitor

Systems, devices, and methods are provided for built-in redundancy in optical devices that output an optical signal, for example, to photonic integrated circuits. The device and systems disclosed herein include a plurality of optical sources coupled to a plurality of waveguides. Each adjacent pair of the plurality of waveguides are coupled to an optical switching devices that comprises an interferometer having a first branch comprising a phase-shift mechanism coupled to one waveguide of the pair of waveguides. A voltage bias can be applied to the phase-shift mechanisms to tune a respective phase difference and direct an optical signal from any of the plurality of optical sources to the output end of the optical device. According to various examples disclosed herein, the phase-shift mechanisms comprises metal oxide semiconductor (MOS) capacitors.

Optical devices and systems for optical source redundancy

Implementations disclosed herein provide for devices and methods for obtaining parity time (PT) symmetric directional couplers through improved phase tuning, along with separate optical gain and optical loss tuning. The present disclosure integrates phase tuning and optical gain/loss tuning structures into waveguides of directional couplers disclosed herein. In some examples, directional couplers disclosed herein integrate one or more hybrid metal-oxide-semiconductor capacitors (MOSCAPs) formed by a dielectric layer between two semiconductor layers that provide for phase tuning via plasma dispersion and/or carrier accumulation depending on voltage bias polarity, and one or more optically active medium that provide for optical gain or loss tuning depending on voltage bias polarity.

Parity time symmetric directional couplers with phase tuning

Techniques and systems for a semiconductor laser, namely a grating-coupled surface-emitting (GCSE) comb laser, having thermal management for facilitating dissipation of heat, integrated thereon. The thermal management is structured in manner that prevents deformation or damage to the GCSE laser chips included in the semiconductor laser implementation. The disclosed thermal management elements integrated in the laser can include: heat sinks; support bars; solder joints; thermal interface material (TIM); silicon vias (TSV); and terminal conductive sheets. Support bars, for example, having the GCSE laser chip positioned between the bars and having a height that is higher than a thickness of the GCSE laser chip. Accordingly, the heat sink can be placed on top of the support bars such that heat is dissipated from the GCSE laser chip, and the heat sink is separated from directed contact with the GCSE laser chip due to the height of the support bars.

Thermal management for hybrid lasers

Narrow-optical linewidth laser generation devices and methods for generating a narrow-optical linewidth laser beam are provided. One narrow-optical linewidth laser generation devie includes a single-wavelength mirror or multiwavelength mirror (for comb lasers) formed from one or more optical ring resonators coupled with an optical splitter. The optical splitter may in turn be coupled with a quantum dot optical amplifier (QDOA), itself coupled with a phase-tuner. The phase tuner may be further coupled with a broadband mirror. The narrow-optical linewidth laser beam is generated by using a long laser cavity and additionally by using an integrated optical feedback.

Quantum-dot-based narrow optical linewidth single wavelength and comb lasers on silicon

Examples disclosed herein relate to quantum-dot (QD) photonics. In accordance with some of the examples disclosed herein, a QD semiconductor optical amplifier (SOA) may include a silicon substrate and a QD layer above the silicon substrate. The QD layer may include an active gain region to amplify a lasing mode received from an optical signal generator. The QD layer may have a gain recovery time such that the active gain region amplifies the received lasing mode without pattern effects. A waveguide may be included in an upper silicon layer of the silicon substrate. The waveguide may include a mode converter to facilitate optical coupling of the received lasing mode between the QD layer and the waveguide.

Quantum-dot photonics

Examples herein relate to optical systems. In particular, implementations herein relate to an optical system including an optical transmitter configured to transmit optical signals. The optical transmitter includes a first optical source and a second optical source coupled to the first optical source and injection seeded by the first optical source. The optical transmitter further includes an output coupler, the second optical source coupled to the optical coupler via an output waveguide and configured to emit light having multiple different wavelengths through the output waveguide. In some implementations, the second optical source is self-injection seeded.

Injection seeding of a comb laser

Examples herein relate to optical systems. In particular, implementations herein relate to an optical system including an optical transmitter configured to transmit optical signals. The optical transmitter includes a first optical source coupled to an input waveguide and configured to emit light having different wavelengths through the input waveguide. The optical transmitter includes a Mach-Zehnder interferometer that includes a first arm and a second arm. The MZI further includes a first optical coupler configured to couple the emitted light from the input waveguide to the first and second arms and an array of two or more second optical sources coupled to the first arm. Each of the two or more second optical sources are configured to be injection locked to a different respective wavelength of the emitted light transmitted from the first optical source. The MZI further includes a second optical coupler configured to combine the emitted light from the first and second arms after propagating therethrough.

Low drive voltage multi-wavelength transmitter

Examples herein relate to optoelectronic systems or modules. In particular, implementations herein relate to an optoelectronic module or system that includes a substrate having opposing first and second sides and an optoelectronic component having opposing first and second sides flip chip assembled to the substrate. The optoelectronic component is configured to emit at least one optical signal to the substrate, receive at least one optical signal from the substrate, or both. The optoelectronic system further includes an underfill exclusion structure configured to prevent underfill material dispensed between the optoelectronic component and the substrate from flowing into an optical area or path of the at least one optical signal transmitted between the optoelectronic component and the substrate. The underfill exclusion structure is spaced apart from at least one of the optoelectronic component or the substrate.

Optoelectronic device with integrated underfill exclusion structure

Examples disclosed herein relate to multi-wavelength semiconductor comb lasers. In some examples disclosed herein, a multi-wavelength semiconductor comb laser may include a waveguide included in an upper silicon layer of a silicon-on-insulator (SOI) substrate. The comb laser may include a quantum dot (QD) active gain region above the SOI substrate defining an active section in a laser cavity of the comb laser and a dispersion tuning section included in the laser cavity to tune total cavity dispersion of the comb laser.

Multi-wavelength semiconductor comb lasers

A Dense Wavelength Division Multiplexing (DWDM) photonic integration circuit (PIC) that implements a DWDM system, such as a transceiver, is described. The DWDM PIC architecture includes photonic devices fully integrating on a single manufacturing platform. The DWDM PIC has a multi-wavelength optical laser, a quantum dot (QD) laser with integrated heterogeneous metal oxide semiconductor (H-MOS) capacitor, integrated on-chip. The multi-wavelength optical laser can be a symmetric comb laser that generates two equal outputs of multi-wavelength light. Alternatively, the DWDM PIC can be designed to interface with a stand-alone multi-wavelength optical laser that is off-chip. In some implementations, the DWDM PIC integrates multiple optimally designed photonic devices, such as a silicon geranium (SiGe) avalanche photodetector (APD), an athermal H-MOS wavelength splitter, a QD photodetector, and a heterogenous grating coupler. Accordingly, fabricating the DWDM PIC includes a unique III-V to silicon bonding process, which is adapted for its use of SiGe APDs.

Dense wavelength division multiplexing (DWDM) photonic integration platform

Improved systems and methods are provided to implement coherent communication. The system includes an interposer to route the components of an integrated photonic circuit. The interposer provides an interface to couple the components of the integrated photonic circuit including an optical source, modulator, coherent transmitter, coherent receiver, and interconnects therebetween. The optical source can be a grating-coupled surface-emitting laser (GCSEL). The GCSEL splits an optical signal into two symmetrical optical signals that are directed by a waveguide to a coherent transmitter and/or a coherent receiver of the integrated photonic circuit. Coherent communication is maintained and the need for a second laser in the coherent receiver is avoided through the structure of the GCSEL granting dual functional to the optical source.

Coherent optical source based on packaged GCSEL

An example system for multi-wavelength optical signal splitting is disclosed. The example disclosed herein comprises a first splitter, a second splitter, and a modulator. The system receives a multi-wavelength optical signal and an electrical signal, wherein the multi-wavelength optical signal comprises a plurality of optical wavelengths and has a power level. The first splitter is to split the plurality of optical wavelengths into a plurality of optical wavelength groups. The second splitter is to split the multi-wavelength optical signal or the plurality of optical wavelength groups into a plurality of lower power signal groups. The modulator is to encode the electrical signal into the plurality of optical wavelength groups, the plurality of lower power signal groups, or a combination thereof.

Multi-wavelength optical signal splitting

Techniques and circuitry for a semiconductor laser with enhanced lasing wavelengths stabilization are described. A semiconductor laser can generate an optical signal (e.g., single or multi-wavelength), for use in a Dense Wavelength Division Multiplexing (DWDM) interconnect system. The stabilization circuitry can include temperature sensor circuitry that measures an operational temperature of the semiconductor laser, and a feedback controller that can determine a temperature-induced wavelength shift that may be experienced by the multi-wavelength optical signal based on the laser's temperature. The feedback controller is also configured to generate a compensation signal that is determined to cause a complimentary shift in the multi-wavelength optical signal, where the complimentary shift can compensate for the temperature-induced wavelength shift. An integrated MOS capacitor of the laser can be charged by the signal in a manner that effectuates the complimentary shift and tunes the multi-wavelength optical signal to compensate for temperature-induced shift, thereby enhancing stabilization.

Temperature sensor integrated with MOS capacitor for stabilizing lasers

A quantum-dot based avalanche photodiode (QD-APD) may include a silicon substrate and a waveguide on which a quantum dot (QD) stack of layers is formed having a QD light absorption layer, a charge multiplication layer (CML), and spacer layers. The QD stack may be formed within a p-n junction. The waveguide may include a mode converter to facilitate optical coupling and light transfer from the waveguide to the QD light absorption layer. The QD absorption layer and the CML layer may be combined or separate layers. The CML may generate electrical current from the absorbed light with more than 100% quantum efficiency when the p-n junction is reverse-biased.

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Palo Alto, CA, United States of America

Geza Kurczveil