Abstract: Methods, circuits, and techniques for reflection cancellation. Laser output is tapped. A tapped portion of the laser output is phase shifted to generate a feedback signal, with the feedback signal being out-of-phase with a parasitic reflection of the laser output. The feedback signal is directed towards the laser such that the parasitic reflection and feedback signal are superpositioned before entering the laser. A magnitude and a phase of the feedback signal are such that superposition of the feedback signal and the parasitic reflection results in a resulting signal of lower magnitude than the parasitic reflection alone. During laser operation, a magnitude of the resulting signal is monitored and, as the parasitic reflection varies, the magnitude of the resulting signal is adjusted by adjusting at least one of the magnitude and the phase of the feedback signal in response to the monitoring of the resulting signal.

Abstract: A sensor architecture that uses fixed wavelength light and tunes a wavelength dependent response of a sensor may be used for detecting analytes in a wide range of applications. The sensor architecture is based on optical resonators or interferometers comprising optical waveguides. A resonance wavelength and/or transmission/reflection spectrum are affected by presence of an analyte adsorbed on a surface of the waveguide, and a setting of a phase modulator. The sensors include a sensor portion where part of the waveguide is exposed to a sample for sensing, and a phase modulator part. The phase modulator part may include a heater that is controlled to tune, or sweep, or modulate the resonant wavelength and/or spectrum of the sensor.

Abstract: An apparatus for facilitating electromagnetic wave resonator tuning is disclosed, including first, second, and third spaced apart resonator portions, the second portion disposed between the first and third to form an electromagnetic wave resonator having a resonant frequency, wherein the first and second portions define a first volume therebetween and the second and third define a second volume therebetween, a first actuator coupled to the first portion, the second, or both, the first actuator configured to adjust a width of the first volume, and a second actuator coupled to the second portion, the third, or both, the second actuator configured to adjust a width of the second volume, wherein the actuators are configured to decrease the widths of the first and second volumes or increase the widths of the first and second volumes to adjust the resonant frequency of the resonator. Other apparatuses, methods, and systems are also disclosed.

Abstract: Systems and methods for fabricating a semiconductor chip with an integrated laser diode (or other optical component). An example method may comprise fabricating a recess shaped to receive the optical component. The method may also comprise metallizing at least one surface of the recess. The method may also comprise coupling the optical component to the at least one metallized surface of the recess. The component may comprise a laser diode comprising a p-type semiconductor and an n-type semiconductor. The n-type semiconductor may be electrically coupled to the at least one metallized surface of the recess. The method may also comprise optically coupling an optical output of the laser diode (or other optical component) to an optical input of a photonic interface of the chip with a photonic wire bond and/or at least one polymer lens.

Abstract: A sensor architecture that uses fixed wavelength light and tunes a wavelength dependent response of a sensor may be used for detecting analytes in a wide range of applications. The sensor architecture is based on optical resonators or interferometers comprising optical waveguides. A resonance wavelength and/or transmission/reflection spectrum are affected by presence of an analyte adsorbed on a surface of the waveguide, and a setting of a phase modulator. The sensors include a sensor portion where part of the waveguide is exposed to a sample for sensing, and a phase modulator part. The phase modulator part may include a heater that is controlled to tune, or sweep, or modulate the resonant wavelength and/or spectrum of the sensor.

Abstract: A hybrid electronic optical chip has a first photonic element with which a first diode is associated, a second photonic element with which a second diode is associated and a common electrical driver connected to the first and second diodes by a common electrical connection with opposite polarity. The electrical driver generates a common electrical drive signal divided in time into first and second drive signal components for independently driving the first and second photonic elements through the common electrical connection.

Abstract: Methods, circuits, and techniques for reflection cancellation. Laser output is tapped. A tapped portion of the laser output is phase shifted to generate a feedback signal, with the feedback signal being out-of-phase with a parasitic reflection of the laser output. The feedback signal is directed towards the laser such that the parasitic reflection and feedback signal are superpositioned before entering the laser. A magnitude and a phase of the feedback signal are such that superposition of the feedback signal and the parasitic reflection results in a resulting signal of lower magnitude than the parasitic reflection alone. During laser operation, a magnitude of the resulting signal is monitored and, as the parasitic reflection varies, the magnitude of the resulting signal is adjusted by adjusting at least one of the magnitude and the phase of the feedback signal in response to the monitoring of the resulting signal.

Abstract: A hybrid electronic optical chip has a first photonic element with which a first diode is associated, a second photonic element with which a second diode is associated and a common electrical driver connected to the first and second diodes by a common electrical connection with opposite polarity. The electrical driver generates a common electrical drive signal divided in time into first and second drive signal components for independently driving the first and second photonic elements through the common electrical connection.

Abstract: An apparatus for facilitating electromagnetic wave resonator tuning is disclosed, including first, second, and third spaced apart resonator portions, the second portion disposed between the first and third to form an electromagnetic wave resonator having a resonant frequency, wherein the first and second portions define a first volume therebetween and the second and third define a second volume therebetween, a first actuator coupled to the first portion, the second, or both, the first actuator configured to adjust a width of the first volume, and a second actuator coupled to the second portion, the third, or both, the second actuator configured to adjust a width of the second volume, wherein the actuators are configured to decrease the widths of the first and second volumes or increase the widths of the first and second volumes to adjust the resonant frequency of the resonator. Other apparatuses, methods, and systems are also disclosed.

Abstract: A hybrid electronic optical chip has a first photonic element with which a first diode is associated, a second photonic element with which a second diode is associated and a common electrical driver connected to the first and second diodes by a common electrical connection with opposite polarity. The electrical driver generates a common electrical drive signal divided in time into first and second drive signal components for independently driving the first and second photonic elements through the common electrical connection.

Abstract: A method and apparatus for monitoring and feedback control of a photonic switch such as 2×2 Mach-Zehnder Interferometer switch. Optical signals at an input and an output of the switch are monitored via optical taps. A sinusoidal time-varying phase shift is applied to one of the monitoring signals. An optical combiner then combines the monitoring signals. A photodetector monitors output of the optical combiner to provide a feedback signal. The amplitude of the feedback signal due to the time-varying phase shift increases with the amount of input signal present in the output signal. When the input signal is to be routed to the output (e.g. for a bar state), a controller manipulates the switch to maximize feedback signal amplitude. When the input signal is to be routed to a different output (e.g. for a cross state), the controller manipulates the switch to minimize feedback signal amplitude.

Abstract: An optical transmitter including an optical waveguide and N microring resonators (MRRs) coupled to the optical waveguide is provided. In such an optical transmitter each of the N MRRs having a different coupling coefficient determining the amount of coupling to the optical waveguide, wherein N>1. In some embodiments, each of the N MRRs has a different spacing distance from the optical waveguide, wherein the coupling coefficient for each MRR is dependent on the spacing. In some embodiments the optical transmitter further includes an input for receiving N drive signals from a controller, each drive signal shifting the resonant wavelength of the corresponding MRR to control the optical power coupled in the corresponding MRR from the optical waveguide in which an optical signal propagates.

Abstract: A method and apparatus for monitoring and feedback control of a photonic switch such as 2×2 Mach-Zehnder Interferometer switch. Optical signals at an input and an output of the switch are monitored via optical taps. A sinusoidal time-varying phase shift is applied to one of the monitoring signals. An optical combiner then combines the monitoring signals. A photodetector monitors output of the optical combiner to provide a feedback signal. The amplitude of the feedback signal due to the time-varying phase shift increases with the amount of input signal present in the output signal. When the input signal is to be routed to the output (e.g. for a bar state), a controller manipulates the switch to maximize feedback signal amplitude. When the input signal is to be routed to a different output (e.g. for a cross state), the controller manipulates the switch to minimize feedback signal amplitude.

Abstract: A temperature compensated carrier effect switching cell controls phase shifts to compensate for phase errors induced by temperature difference between arms of the switching cell. The temperature difference may be generated by driving the carrier effect region of the switching cell. Temperature sensors within the arms of the switching cell provide signals indicative of the temperature difference.

Abstract: A hybrid electronic optical chip has a first photonic element with which a first diode is associated, a second photonic element with which a second diode is associated and a common electrical driver connected to the first and second diodes by a common electrical connection with opposite polarity. The electrical driver generates a common electrical drive signal divided in time into first and second drive signal components for independently driving the first and second photonic elements through the common electrical connection.

Abstract: An optical device comprises a first optical coupler configured to receive a light signal and provide a first output and a second output, a first optical waveguide in optical communication with the first output and configured to provide a first optical path for a first portion of the light signal, and a second optical waveguide in optical communication with the second output and configured to provide a second optical path for a second portion of the light signal, wherein the first optical waveguide is configured to provide a phase differential between the first optical path and the second optical path, wherein the second optical waveguide is positioned according to a lateral thermal diffusion length associated with the first optical waveguide, and wherein the lateral thermal diffusion length is a spreading distance of a thermal effect in a direction about perpendicular to the first optical path.

Abstract: The disclosure demonstrates n-doped resistive heaters in silicon waveguides showing photoconductive effects with high responsivities on the order of 100 mA/W. These photoconductive heaters, integrated into microring resonator (MRR)-based filters, can be used to automatically tune and stabilize the filters' resonance wavelength to the input laser-wavelength. This is achieved without requiring dedicated defect implantations, additional material depositions, dedicated photodetectors, or optical power tap-outs. Series-coupled higher-order MRR-based filters can be automatically tuned by sequentially aligning the resonance of each MRR to the laser-wavelength by using photoconductive heaters to monitor the light intensity in each MRR. Embodiments allow for the automatic wavelength stabilization of MRR-based optical circuits.

Abstract: An optical device includes first and second waveguide phase arms each having optically coupled parallel sections of waveguides, the parallel sections of each one of the waveguide phase arms being dissimilar to reduce crosstalk. The device further includes a tunable element for applying a phase shift to an optical signal traversing the first phase arm. The waveguides of the parallel sections may have dissimilar dimensions, e.g. may vary in width, thickness, or both. The waveguides adjacent the tunable element may be suspended and/or underetched to improve thermal isolation and accordingly reduce power consumption of the optical device.

Abstract: An optical device comprises a first optical coupler configured to receive a light signal and provide a first output and a second output, a first optical waveguide in optical communication with the first output and configured to provide a first optical path for a first portion of the light signal, and a second optical waveguide in optical communication with the second output and configured to provide a second optical path for a second portion of the light signal, wherein the first optical waveguide is configured to provide a phase differential between the first optical path and the second optical path, wherein the second optical waveguide is positioned according to a lateral thermal diffusion length associated with the first optical waveguide, and wherein the lateral thermal diffusion length is a spreading distance of a thermal effect in a direction about perpendicular to the first optical path.