Abstract: An integrated circuit is described. This integrated circuit includes an optical waveguide defined in a semiconductor layer, and a dielectric optical waveguide disposed on the semiconductor layer and that overlaps a region of the optical waveguide. Moreover, the dielectric optical waveguide includes an optical device (such as a mirror) on a facet separating a first portion of the dielectric optical waveguide and a second portion of the dielectric optical waveguide. The facet may be at an angle relative to a plane of the dielectric optical waveguide and may include a metal layer. During operation, an optical signal conveyed by the optical waveguide is evanescent coupled to the dielectric optical waveguide. Then, the optical signal may be reflected by the optical device. For example, the angle of the facet may be 45°, so that the optical signal is reflected normal to the plane of the dielectric optical waveguide.

Abstract: An optically switched network system includes an optical switch with N inputs and N outputs that connects N end-nodes and is structured to transmit N wavelengths from each of the N inputs to each of the N outputs. The system includes a virtual data plane and a virtual control plane, which both communicate through the optical switch. The virtual data plane provides any-to-all parallel connectivity for data transmissions among the N end-nodes. The N end-nodes are partitioned into two or more subsets, wherein end-nodes in a given source subset transmit data to a given destination subset using wavelengths, which are not used by end-nodes outside of the given source subset to transmit data to the same given destination subset. The virtual control plane includes two or more rings associated with the two or more subsets of end-nodes. Each ring passes through a subset of end-nodes, and is used to communicate arbitration information among arbitration logic located at each end-node in the ring.

Abstract: A high-power packaged laser array that is thermal reflow compatible is described. Notably, a high-power III-V laser array is integrated on a silicon substrate with a matching array of ball lenses, an isolator and a coupler (such as a reflective layer) to achieve an edge-coupled or a surface-normal output laser array. In some embodiments, an isolator with a permanent magnet is used to preserve the magnetic domain or state of the isolator during the thermal reflow(s), which can involve temperatures up to 250 C. In order to relax the misalignment tolerance when integrating with the silicon chip, a laser array with a larger optical mode may be used to increase the output beam size. Moreover, a III-V laser array with an angled output optical waveguide can be used to improve the stability of the lasers at high power.

Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a common optical waveguide, a splitter that splits the optical signal into optical signals, a first pair of resonators that are selectively optically coupled to the common optical waveguide and that are configured to perform modulation and filtering of the optical signals, and a first bus optical waveguide that is selectively optically coupled to the first pair of resonators. Furthermore, resonance wavelengths of the resonators may be offset from each other with a (e.g., fixed) separation approximately equal or corresponding to a modulation amplitude, and a reflectivity of the first pair of resonators may be approximately independent of the modulation.

Abstract: An optical source may include an optical gain chip that provides an optical signal and that is optically coupled to an SOI chip. The optical gain chip may include a reflective layer. Moreover, the SOI chip may include: a first optical waveguide, a first ring resonator that selectively optically coupled to a second optical waveguide and that performs phase modulation and filtering of the optical signal, the second optical waveguide, an amplitude modulator, and an output port. Note that the reflective layer in the optical gain chip and the amplitude modulator may define an optical cavity. Furthermore, a resonance of the first ring resonator may be aligned with a lasing wavelength, and the resonance of the first ring resonator and a resonance of the amplitude modulator may be offset from each other. Additionally, modulation of the first ring resonator and the amplitude modulator may be in-phase with each other.

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 source includes semiconductor optical amplifiers, with a semiconductor other than silicon, which provide an optical gain medium. Moreover, a photonic chip in the optical source, which is optically coupled to the semiconductor optical amplifiers, includes ring resonators that selectively pass corresponding optical signals having carrier wavelengths provided by the semiconductor optical amplifiers, where a given ring resonator and a reflector on one of the semiconductor optical amplifier defines an optical cavity, and the ring resonators have different radii with associated resonance wavelengths corresponding to the carrier wavelengths.

Abstract: An integrated optical device includes a photo-detector (such as germanium) optically coupled to an optical waveguide. This photo-detector is deposited on the optical waveguide, and an optical signal propagating in the optical waveguide may be evanescently coupled to the photo-detector. In order to increase the absorption length of the photo-detector, a mirror (such as a distributed Bragg reflection grating) is included in the optical waveguide near the end of the photo-detector. This mirror reflects the optical signal back toward the photo-detector, thereby increasing the absorption of the optical signal by the photo-detector. In addition, absorption may be reduced by using electrical contacts that are electrically coupled to the photo-detector at locations where the optical mode of the optical signal is largely in the underlying optical waveguide, and by using a fingered metal layer to couple to the electrical contacts.

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: A reflectivity test circuit is described. The reflectivity test circuit includes a symmetric structure that cancels errors in the reflectivity measurements. In particular, the reflectivity test circuit includes an optical waveguide that is optically coupled to two optical ports and two optical couplers. The optical couplers are optically coupled to adjacent optical waveguides, at least one of which is optically coupled to a third optical port and the mirror. Moreover, a length of the optical waveguide is chosen to match the round-trip optical path length in at least the one of the adjacent optical waveguides. During operation, control logic determines the reflectivity of the mirror based at least on a ratio of an optical power measured on one of the two optical ports to an input optical power on the third optical port.

Abstract: An optically switched network system includes an optical switch with N inputs and N outputs that connects N end-nodes and is structured to transmit N wavelengths from each of the N inputs to each of the N outputs. The system includes a virtual data plane and a virtual control plane, which both communicate through the optical switch. The virtual data plane provides any-to-all parallel connectivity for data transmissions among the N end-nodes. The N end-nodes are partitioned into two or more subsets, wherein end-nodes in a given source subset transmit data to a given destination subset using wavelengths, which are not used by end-nodes outside of the given source subset to transmit data to the same given destination subset. The virtual control plane includes two or more rings associated with the two or more subsets of end-nodes. Each ring passes through a subset of end-nodes, and is used to communicate arbitration information among arbitration logic located at each end-node in the ring.

Abstract: An integrated laser that provides multiple outputs includes a reflective silicon optical amplifier (RSOA) having a reflective end with a reflective coating and an interface end. It also includes an optical waveguide optically coupled to the RSOA. A distributed-Bragg-reflector (DBR) ring resonator is also optically coupled to the optical waveguide, wherein the DBR ring resonator partially reflects a wavelength of the optical signal from the optical waveguide, thereby causing balanced light to flow in clockwise and counter-clockwise directions inside the DBR ring resonator. The integrated laser additionally includes an output waveguide having 2*N ends that function as two outputs, wherein the output waveguide is optically coupled to the DBR ring resonator, which causes balanced light to flow in two directions in the output waveguide, thereby causing the 2*N outputs to provide balanced power.

Abstract: The disclosed embodiments provide an optically switched network system. This system includes a passive optical switch with N inputs and N outputs, which can communicate different wavelengths from each of the N inputs to each of the N outputs. It also includes N end-nodes, and N pairs of optical fibers, wherein each pair connects one of the N end-nodes to one of the N inputs and one of the N outputs. The optically switched network is organized into a virtual data plane and a virtual control plane, which both communicate through the same underlying physical network. The virtual data plane provides any-to-all parallel connectivity for data transmissions among the N end-nodes. The virtual control plane is organized as a ring that serially connects the N end-nodes, wherein the ring communicates arbitration information among distributed-arbitration logic at each of the N end-nodes.

Abstract: The disclosed embodiments provide an apparatus for connecting one or more optical fibers to an optoelectronic system. This apparatus includes a packaged optoelectronic module (POeM) comprising an optical connector, a silicon photonic (SiP) chip, an integrated circuit (IC) chip, at least one laser chip and a package substrate. The apparatus also includes an assembly adapter enclosing the POeM, wherein the assembly adapter includes a mechanical transfer (MT) ferrule cavity, which includes one or more coarse-alignment structures to guide an MT ferrule enclosing at least one optical fiber during assembly of the apparatus. The assembly adapter is comprised of a solder-reflow-compatible material to facilitate bonding the assembly adapter to a circuit board.

Abstract: The disclosed embodiments relate to the design of a hybrid laser comprising a shared ring mirror coupled to a pair of buses by a 3 dB coupler (also referred to as a “symmetric splitter”), which is described in more detail below. Each bus is also coupled to an array of ring filters, wherein each ring filter couples an associated reflective silicon optical amplifier (RSOA) to the shared ring mirror and in doing so forms a Verniered ring pair with the shared ring mirror. The resulting system provides a comb source with redundant channels that can provide individual outputs or a shared output. This hybrid laser provides a significant improvement over existing comb-based lasers by providing redundancy for at least one laser channel.

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 integrated laser that provides multiple outputs includes a reflective silicon optical amplifier (RSOA) having a reflective end with a reflective coating and an interface end. It also includes an optical waveguide optically coupled to the RSOA. A distributed-Bragg-reflector (DBR) ring resonator is also optically coupled to the optical waveguide, wherein the DBR ring resonator partially reflects a wavelength of the optical signal from the optical waveguide, thereby causing balanced light to flow in clockwise and counter-clockwise directions inside the DBR ring resonator. The integrated laser additionally includes an output waveguide having 2*N ends that function as two outputs, wherein the output waveguide is optically coupled to the DBR ring resonator, which causes balanced light to flow in two directions in the output waveguide, thereby causing the 2*N outputs to provide balanced power.