Abstract: In one example embodiment, an optical circuit for optical modulation of light may include an input waveguide including a first thickness, an optical modulator including a second thickness, and a tapered transition that optically couples the optical modulator and the input waveguide. The second thickness may be smaller than the first thickness. The tapered transition may adiabatically transform the optical mode of the input waveguide to the optical modulator.

Abstract: In one example embodiment, an optical circuit for optical modulation of light may include an input waveguide including a first thickness, an optical modulator including a second thickness, and a tapered transition that optically couples the optical modulator and the input waveguide. The second thickness may be smaller than the first thickness. The tapered transition may adiabatically transform the optical mode of the input waveguide to the optical modulator.

Abstract: Disclosed are a system and method for determining a metric and/or indicator of a reliability of a blood glucose sensor in providing glucose measurements. In one aspect, the metric and/or indicator may be computed based, at least in part, on an observed trend associated with signals generated by the blood glucose sensor.

Abstract: In one example embodiment, an integrated silicon photonic wavelength division demultiplexer includes an input waveguide, an input port, a plurality of output waveguides, a plurality of output ports, a first auxiliary waveguide, and a plurality of auxiliary waveguides. The input waveguide may be formed in a first layer and having a first effective index n1. The input port may be optically coupled to the input waveguide. The output waveguides may be formed in the first layer and may have the first effective index n1. Each of the output ports may be optically coupled to a corresponding output waveguide. The first auxiliary waveguide may be formed in a second layer below the input waveguide in the first layer. The first auxiliary waveguide may have a second effective index n2 and may have two tapered ends, and n2 may be higher than n1.

Abstract: An optical waveguide may include a silicon portion and a silicon nitride portion positioned over the silicon portion. The silicon portion may include a taper that decreases a width of the silicon portion. The optical waveguide may include a transition between a loaded single mode or multimode waveguide to a single mode waveguide. The silicon nitride portion may confine optical signals traveling through the optical waveguide in the silicon portion.

Abstract: Disclosed are methods, apparatuses, etc. for glucose sensor signal stability analysis. In certain example embodiments, a series of samples of at least one sensor signal that is responsive to a blood glucose level of a patient may be obtained. Based at least partly on the series of samples, at least one metric may be determined to assess an underlying trend of a change in responsiveness of the at least one sensor signal to the blood glucose level of the patient over time. A reliability of the at least one sensor signal to respond to the blood glucose level of the patient may be assessed based at least partly on the at least one metric assessing the underlying trend. Other example embodiments are disclosed herein.

Abstract: A processing apparatus is provided that includes an encoder configured to encode current frames of video data using previously encoded reference frames and perform motion searches within a search window about each of a plurality of co-located portions of a reference frame. The processing apparatus also includes a processor configured to determine, prior to performing the motion searches, which locations of the reference frame to reload the search window according to a threshold number of search window reloads using predicted motions of portions of the reference frame corresponding to each of the locations. The processor is also configured to cause the encoder to reload the search window at the determined locations of the reference frame and, for each of the remaining locations of the reference frame, slide the search window in a first direction indicated by the location of the next co-located portion of the reference frame.

Abstract: An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter.

Abstract: In one example embodiment, an integrated silicon photonic wavelength division demultiplexer includes an input waveguide, an input port, a plurality of output waveguides, a plurality of output ports, a first auxiliary waveguide, and a plurality of auxiliary waveguides. The input waveguide may be formed in a first layer and having a first effective index n1. The input port may be optically coupled to the input waveguide. The output waveguides may be formed in the first layer and may have the first effective index n1. Each of the output ports may be optically coupled to a corresponding output waveguide. The first auxiliary waveguide may be formed in a second layer below the input waveguide in the first layer. The first auxiliary waveguide may have a second effective index n2 and may have two tapered ends, and n2 may be higher than n1.

Abstract: An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter.

Abstract: The disclosed embodiments provide a laser source comprising a silicon waveguide formed in a silicon layer, and a cascaded array of hybrid distributed feedback (DFB) lasers formed by locating sections of III-V gain material over the silicon waveguide. Each DFB laser in the cascaded array comprises a section of III-V gain material located over the silicon waveguide, wherein the section of III-V gain material includes an active region that generates light, and a Bragg grating located between the III-V gain material and the silicon waveguide. This Bragg grating has a resonance frequency within a gain bandwidth of the section of III-V material and is transparent to frequencies that differ from the resonance frequency. Moreover, each DFB laser has a hybrid mode that resides partially in the III-V gain material and partially in silicon.

Abstract: An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter.

Abstract: An optical transmitter includes: a set of reflective silicon optical amplifiers (RSOAs), a set of ring modulators, a shared broadband reflector, a set of intermediate waveguides, and a shared waveguide. Each intermediate waveguide channels light from an RSOA in proximity to an associated ring modulator to cause optically coupled light to circulate in the associated ring modulator. The shared waveguide is coupled to the shared broadband reflector, and passes in proximity to the set of ring modulators, so that light circulating in each ring modulator causes optically coupled light to flow in the shared optical waveguide. During operation, each RSOA forms a lasing cavity with the shared broadband reflector, wherein each lasing cavity has a different wavelength, which is determined by a resonance of the associated ring modulator. The different wavelengths are combined in the shared waveguide to produce a combined output.

Abstract: The disclosed embodiments provide a laser source comprising a silicon waveguide formed in a silicon layer, and a cascaded array of hybrid distributed feedback (DFB) lasers formed by locating sections of III-V gain material over the silicon waveguide. Each DFB laser in the cascaded array comprises a section of III-V gain material located over the silicon waveguide, wherein the section of III-V gain material includes an active region that generates light, and a Bragg grating located between the III-V gain material and the silicon waveguide. This Bragg grating has a resonance frequency within a gain bandwidth of the section of III-V material and is transparent to frequencies that differ from the resonance frequency. Moreover, each DFB laser has a hybrid mode that resides partially in the III-V gain material and partially in silicon.

Abstract: An optical transmitter includes: a set of reflective silicon optical amplifiers (RSOAs), a set of ring modulators, a shared broadband reflector, a set of intermediate waveguides, and a shared waveguide. Each intermediate waveguide channels light from an RSOA in proximity to an associated ring modulator to cause optically coupled light to circulate in the associated ring modulator. The shared waveguide is coupled to the shared broadband reflector, and passes in proximity to the set of ring modulators, so that light circulating in each ring modulator causes optically coupled light to flow in the shared optical waveguide. During operation, each RSOA forms a lasing cavity with the shared broadband reflector, wherein each lasing cavity has a different wavelength, which is determined by a resonance of the associated ring modulator. The different wavelengths are combined in the shared waveguide to produce a combined output.

Abstract: An integrated circuit that includes a wavelength-filter layer stack (which may include silicon oxynitride) and an optical substrate (such as a silicon-on-insulator platform) is described. During operation, an optical signal received from an optical fiber or an optical waveguide is wavelength filtered into a set of wavelength-filter optical waveguides by an optical multiplexer/demultiplexer (such as an Echelle grating and/or an array waveguide grating) in the wavelength-filter layer stack. Then, wavelength-filtered optical signals are optically coupled to the optical substrate, where they are received using photodetectors. Alternatively, modulators in the optical substrate modulate wavelength-filtered modulated optical signals, which are then optically coupled to the set of wavelength-filter optical waveguides in the wavelength-filter layer stack.

Abstract: An optical transmitter includes a reflective semiconductor optical amplifier (RSOA) coupled to an input end of a first optical waveguide. An end of the first optical waveguide provides a transmitter output for the optical transmitter. Moreover, a section of the first optical waveguide between the input end and the output end is optically coupled to a ring modulator that modulates an optical signal based on an electrical input signal. A passive ring filter (or a 1×N silicon-photonic switch and a bank of band reflectors) is connected to provide a mirror that reflects light received from the second optical waveguide back toward the RSOA to form a lasing cavity. Moreover, the ring modulator and the passive ring filter have different sizes, which causes a Vernier effect that provides a large wavelength tuning range for the lasing cavity in response to tuning the ring modulator and the passive ring filter.

Abstract: The disclosed embodiments provide a system that implements an optical interface. The system includes a semiconductor chip with a silicon layer, which includes a silicon waveguide, and an interface layer (which can be comprised of SiON) disposed over the silicon layer, wherein the interface layer includes an interface waveguide. The system also includes an optical coupler that couples an optical signal from the silicon waveguide in the silicon layer to the interface waveguide in the interface layer, wherein the interface waveguide channels the optical signal in a direction parallel to a top surface of the semiconductor chip. The system additionally includes a mirror, which is oriented to reflect the optical signal from the interface waveguide in a surface-normal direction so that the optical signal exits the top surface of the semiconductor chip.

Abstract: The disclosed embodiments provide a system that implements an optical interface. The system includes a semiconductor chip with a silicon layer, which includes a silicon waveguide, and an interface layer (which can be comprised of SiON) disposed over the silicon layer, wherein the interface layer includes an interface waveguide. The system also includes an optical coupler that couples an optical signal from the silicon waveguide in the silicon layer to the interface waveguide in the interface layer, wherein the interface waveguide channels the optical signal in a direction parallel to a top surface of the semiconductor chip. The system additionally includes a mirror, which is oriented to reflect the optical signal from the interface waveguide in a surface-normal direction so that the optical signal exits the top surface of the semiconductor chip.

Abstract: A dual-ring-modulated laser includes a gain medium having a reflective end coupled to a gain-medium reflector and an output end coupled to a reflector circuit to form a lasing cavity. This reflector circuit comprises: a first ring modulator; a second ring modulator; and a shared waveguide that optically couples the first and second ring modulators. The first and second ring modulators have resonance peaks, which are tuned to have an alignment separation from each other. During operation, the first and second ring modulators are driven in opposing directions based on the same electrical input signal, so the resonance peaks of the first and second ring modulators shift wavelengths in the opposing directions during modulation. The modulation shift for each of the resonance peaks equals the alignment separation, so the resonance peaks interchange positions during modulation to cancel out reflectivity changes in the lasing cavity caused by the modulation.