Abstract: A distributed traveling-wave Mach-Zehnder modulator driver having a plurality of modulation stages that operate cooperatively (in-phase) to provide a signal suitable for use in a 100 Gb/s optical fiber transmitter at power levels that are compatible with conventional semiconductor devices and conventional semiconductor processing is described.

Abstract: An integrated optical device fabricated in the back end of line process located within the vertical span of the metal stack and having one or more advantages over a corresponding integrated optical device fabricated in the silicon on insulator layer.

Abstract: A composite optical waveguide is constructed using an array of waveguide cores, in which one core is tapered to a larger dimension, so that all the cores are used as a composite input port, and the one larger core is used as an output port. In addition, transverse couplers can be fabricated in a similar fashion. The waveguide cores are preferably made of SiN. In some cases, a layer of SiN which is provided as an etch stop is used as at least one of the waveguide cores. The waveguide cores can be spaced away from a semiconductor layer so as to minimize loses.

Abstract: A hybrid single or multi-wavelength laser using an optical gain element, such as a semiconductor optical amplifier (SOA), for example a QD RSOA, and a semiconductor, e.g. silicon, photonics chip is demonstrated. A plurality, e.g. four, lasing modes at a predetermined, e.g. 2 nm, spacing and less than 3 dB power non-uniformity may be observed, with over 20 mW of total output power. Each lasing peak can be successfully modulated at 10 Gb/s. At 10?9 BER, the receiver power penalty is less than 2.6 dB compared to a conventional commercial laser. An expected application is the provision of a comb laser source for WDM transmission in optical interconnection systems.

Abstract: Described are various embodiments of a dual optical modulator, system and method. In one embodiment, an optical modulator modulates an input optical signal having a designated optical frequency. The modulator comprises first and second tunable modulators operable around the optical frequency and operatively disposed between a bus waveguide path and an opposed waveguide path. The modulator further comprises a relative optical phase-shifter optically coupled between the tunable modulators so to impart a relative optical phase shift between the bus waveguide path and the opposed waveguide path. The tunable modulators are respectively driveable to modulate a respective resonance thereof in complimentary directions relative to the optical frequency and thereby resonantly redirect a selectable portion of the input optical signal along the opposed waveguide path such that the relative optical phase shift is imparted thereto for output.

Abstract: Back scattering in an optical waveguide at an operating wavelength is controlled by adjusting an optical phase of light propagating in the waveguide at one or more locations along the waveguide. A portion of the back scattered light is tapped off near an input port and coupled into a photodetector. A controller detects changes in the photodetector signal and adjusts an optical phase tuner configured to control the optical phase of light in the waveguide at the selected location or locations. The optical phase tuner may be configured to vary the refractive index of at least a portion of the waveguide.

Abstract: Two semiconductor chips are optically aligned to form a hybrid semiconductor device. Both chips have optical waveguides and alignment surface positioned at precisely-defined complementary vertical offsets from optical axes of the corresponding waveguides, so that the waveguides are vertically aligned when one of the chips is placed atop the other with their alignment surface abutting each other. The position of the at least one of the alignment surface in a layer stack of its chip is precisely defined by epitaxy. The chips are bonded at offset bonding pads with the alignment surfaces abutting in the absence of bonding material therebetween.

Abstract: A high data rate, high sensitivity, low power optical link using low-bandwidth components and low-bandwidth E/O drivers and receivers and method of building same. The method is based on the idea of making the optical part of the link look like a bandwidth limited lossy electrical channel, so that the powerful equalization methods used in the wireline electrical links can be applied to recover the transmitted data in a situation with low bandwidth and/or high loss and strong inter-symbol interference. Linear and non-linear optical channel components, E/O drivers and receivers can benefit from the apparatus and the methods of the invention.

Abstract: A Ge-on-Si photodetector constructed without doping or contacting Germanium by metal is described. Despite the simplified fabrication process, the device has responsivity of 1.24 A/W, corresponding to 99.2% quantum efficiency. Dark current is 40 nA at ?4 V reverse bias. 3-dB bandwidth is 30 GHz.

Abstract: A low loss high extinction ratio on-chip polarizer is disclosed. The polarizer is formed of a mode convertor followed by a mode squeezer and a dump waveguide, and may be configured to pass a desired waveguide mode and reject undesired modes. An embodiment is described that transmits a TE0 mode while blocking a TM0 mode by converting it into a higher-order TEn mode in a waveguide taper, squeezing out the TEn mode in a second waveguide taper to lessen its confinement, and then dumping the TEn mode in a waveguide bend that is configured to pass the TE0 mode.

Abstract: A light shield may be formed in photonic integrated circuit between integrated optical devices of the photonic integrated circuit. The light shield may be built by using materials already present in the photonic integrated circuit, for example the light shield may include metal walls and doped semiconductor regions. Light-emitting or light-sensitive integrated optical devices or modules of a photonic integrated circuit may be constructed with light shields integrally built in.

Abstract: A hybrid external cavity multi-wavelength laser using a QD RSOA and a silicon photonics chip is demonstrated. Four lasing modes at 2 nm spacing and less than 3 dB power non-uniformity were observed, with over 20 mW of total output power. Each lasing peak can be successfully modulated at 10 Gb/s. At 10?9 BER, the receiver power penalty is less than 2.6 dB compared to a conventional commercial laser. An expected application is the provision of a comb laser source for WDM transmission in optical interconnection systems.

Abstract: A distributed traveling-wave Mach-Zehnder modulator driver having a plurality of modulation stages that operate cooperatively (in-phase) to provide a signal suitable for use in a 100 Gb/s optical fiber transmitter at power levels that are compatible with conventional semiconductor devices and conventional semiconductor processing is described.

Abstract: A low loss high extinction ratio on-chip polarizer. The polarizer includes an input waveguide taper having an outer waveguiding region that widens in the direction of light propagation along at least a portion of the taper length, and a core waveguiding region that narrows in the direction of light propagation along at least a portion of the taper length, so as to selectively squeeze out light of undesired modes into the outer regions while preserving light of a desired mode in the waveguide core. An output filter section is provided to prevent light from reentering the output waveguide after being squeezed out. An integrated light absorber/deflector may be coupled to the outer waveguiding regions.

Abstract: A compact, low-loss and wavelength insensitive Y-junction for submicron silicon waveguides. The design was performed using FDTD and particle swarm optimization (PSO). The device was fabricated in a 248 nm CMOS line. Measured average insertion loss is 0.28±0.02 dB across an 8-inch wafer. The device footprint is less than 1.2 ?m×2 ?m, orders of magnitude smaller than MMI and directional couplers.

Abstract: A composite optical waveguide is constructed using an array of waveguide cores, in which one core is tapered to a larger dimension, so that all the cores are used as a composite input port, and the one larger core is used as an output port. In addition, transverse couplers can be fabricated in a similar fashion. The waveguide cores are preferably made of SiN. In some cases, a layer of SiN which is provided as an etch stop is used as at least one of the waveguide cores. The waveguide cores can be spaced away from a semiconductor layer so as to minimize loses.

Abstract: A distributed traveling-wave Mach-Zehnder modulator driver having a plurality of modulation stages that operate cooperatively (in-phase) to provide a signal suitable for use in a 100 Gb/s optical fiber transmitter at power levels that are compatible with conventional semiconductor devices and conventional semiconductor processing is described.

Abstract: A Ge-on-Si photodetector constructed without doping or contacting Germanium by metal is described. Despite the simplified fabrication process, the device has responsivity of 1.24 A/W, corresponding to 99.2% quantum efficiency. Dark current is 40 nA at ?4 V reverse bias. 3-dB bandwidth is 30 GHz.

Abstract: Otherwise-unused metal pads are utilized for mechanically marking an identification number on each chip in each reticle of each semiconductor wafer. A chip-specific marking pattern is scribed into selected metal pads using a standard commercial wafer probe controlled by a custom-built controller to direct the probe or probe stage to implement the pattern. Visual inspection (manual and automated) may then be used for die identification based on the probe-marked pattern, including incorporating the visual inspection of these pads into the product building process.

Abstract: A multimode interference (MMI) coupler with an MMI region of curved edges, and a method of design and manufacturing by using a computerized optimization algorithm to determine a favorable set of segment widths for the MMI region for a predefined set of coupler design parameters.