Abstract: An optical modulator includes a first Radio Frequency (RF) line and a second RF line; an optical waveguide along a length of the modulator with an input and an output; and a plurality of segments along the length including a first set of segments, a single RF line crossing, and a second set of segments, wherein the first set of segments and the second set of segments have an inversion of their respective orientation at the RF line crossing, and wherein the RF line crossing is located off center relative to the plurality of segments, wherein each of the first RF line and the second RF line extend along the length and cross one another at the RF line crossing.

Abstract: A carrier depletion-based Silicon Photonic (SiP) modulator using capacitive coupling includes a high-k dielectric material in or on slabs, between a rib. A capacitance (Ck) of the high-k dielectric material is larger than a capacitance (Cpn) of the rib, thereby reducing the high frequency impedance and improving bandwidth of the modulator. A modulator includes a first electrode; a first slab connected to the first electrode at a first end; a rib connected to the first slab at a second end of the first slab; a second slab connected to the rib at a first end; a second electrode connected to the second slab at a second end of the second slab; and a high-k dielectric material disposed in or on a portion of each of the first slab and the second slab, thereby enabling capacitive coupling.

Abstract: A coherent receiver includes a receive signal path including i) an input configured to connect a receive signal, ii) one or more signal paths connected to the input and to one or more optical hybrids, and iii) a variable optical attenuator (VOA) in each of the one or more signal paths; and a local oscillator (LO) signal path including i) an input configured to connect to an LO and the one or more optical hybrids, and ii) one or more complementary VOAs located between the input and the one or more optical hybrids, wherein the one or more complementary VOAs are configured to cancel any phase changes from the VOA in each of the one or more signal paths. The VOA in each of the one or more signal paths and the one or more complementary VOAs can be p-i-n junctions.

Abstract: A first transmission line comprises a first pair of electrodes receiving an electrical drive comprising first and second drive signals, which are loaded by a first series of p-n junctions applying optical phase modulation to respective optical waves propagating over a first section of the first and second optical waveguide arms of an MZI. A second transmission line comprises a second pair of electrodes configured to receive the electrical drive after an electrical signal delay. The second pair of electrodes are loaded by a second series of p-n junctions applying optical phase modulation to the respective optical waves propagating over a second section of the first and second optical waveguide arms after propagation over the first section. An electrode extension structure provides the electrical drive to the second pair of electrodes, and comprises an unloaded transmission line portion imposing the electrical signal delay based on an optical signal delay.

Abstract: A loss-based wavelength meter includes a first photodiode configured to measure power of monochromatic light; and a loss section having a monotonic wavelength dependency, wherein a wavelength of the monochromatic light is determined based on measurements of the first photodiode after the monochromatic light has gone through the loss section. This provides a compact implementation that may be used in integrated optics devices using silicon photonics as well as other embodiments.

Abstract: Driving an optical modulator is described. A control circuit generates first and second input voltages based on a target phase modulation between first and second optical waveguide arms of the optical modulator. An offset control circuit generates first and second offset signals. A linear modulator driver receives the first and second offset signals, generates a first output voltage for biasing the first optical waveguide arm using the first offset signal, and generates a second output voltage for biasing the second optical waveguide arm using the second offset signal. Feedback circuitry can feed the first and second output voltages to the offset control circuit, which can generate the first and second offset signals using the first and second output voltages. The output voltages bias the waveguide arms so the optical modulator operates close to the target phase modulation, even in the presence of manufacturing errors.

Abstract: An optical modulator includes a first Radio Frequency (RF) line and a second RF line; an optical waveguide along a length of the modulator with an input and an output; and a plurality of segments along the length including a first set of segments, a single RF line crossing, and a second set of segments, wherein the first set of segments and the second set of segments have an inversion of their respective orientation at the RF line crossing, and wherein the RF line crossing is located off center relative to the plurality of segments, wherein each of the first RF line and the second RF line extend along the length and cross one another at the RF line crossing.

Abstract: A first transmission line comprises a first pair of electrodes receiving an electrical drive comprising first and second drive signals, which are loaded by a first series of p-n junctions applying optical phase modulation to respective optical waves propagating over a first section of the first and second optical waveguide arms of an MZI. A second transmission line comprises a second pair of electrodes configured to receive the electrical drive after an electrical signal delay. The second pair of electrodes are loaded by a second series of p-n junctions applying optical phase modulation to the respective optical waves propagating over a second section of the first and second optical waveguide arms after propagation over the first section. An electrode extension structure provides the electrical drive to the second pair of electrodes, and comprises an unloaded transmission line portion imposing the electrical signal delay based on an optical signal delay.

Abstract: An integrated circuit comprises: at least one photonic layer that includes one or more optical waveguides; a first optical coupler that couples at least a first optical mode outside of the photonic layer to a first waveguide in the photonic layer; a photonic device that includes one or more ports in the photonic layer; a first multi-port optical coupler that includes three or more ports in the photonic layer, including a first port optically coupled to the first optical coupler, a second port optically coupled to a first port of the photonic device, and a third port optically coupled to a first optical reflector configured to send substantially all optical power emitted from the third port of the first multi-port optical coupler back to the third port of the first multi-port optical coupler.

Abstract: A method of Silicon Selective Epitaxial Growth (SEG) applied to a Silicon on Insulator (SOI) wafer to provide a first region of customized thickness includes with the SOI wafer having a standard thickness, applying a hard mask to a plurality of regions of the SOI wafer including the first region; applying photo-lithography protection to cover the hard mask in all of the plurality of regions except the first region; removing the hard mask in the first region; and performing Silicon SEG in the first region to provide the customized thickness in the first region, wherein the customized thickness is greater than the standard thickness.

Abstract: An integrated circuit comprises: at least one photonic layer that includes one or more optical waveguides; a first optical coupler that couples at least a first optical mode outside of the photonic layer to a first waveguide in the photonic layer; a photonic device that includes one or more ports in the photonic layer; a first multi-port optical coupler that includes three or more ports in the photonic layer, including a first port optically coupled to the first optical coupler, a second port optically coupled to a first port of the photonic device, and a third port optically coupled to a first optical reflector configured to send substantially all optical power emitted from the third port of the first multi-port optical coupler back to the third port of the first multi-port optical coupler.

Abstract: An optical modulator includes multiple segments including modulator segments and a Radio Frequency (RF) crossing segment where RF lines extending a length of the modulator cross one another. The present disclosure includes optimization of one or more of a geometry of the RF crossing and a location of the RF crossing segment along the length. The geometry is selected so that the RF crossing segment appears as another segment having similar characteristics as modulator segments. The location of the RF crossing segment is selected to balance out fabrication error and phase efficiency.

Abstract: A carrier depletion-based Silicon Photonic (SiP) modulator using capacitive coupling includes a high-k dielectric material in or on slabs, between a rib. A capacitance (Ck) of the high-k dielectric material is larger than a capacitance (Cpn) of the rib, thereby reducing the high frequency impedance and improving bandwidth of the modulator. A modulator includes a first electrode; a first slab connected to the first electrode at a first end; a rib connected to the first slab at a second end of the first slab; a second slab connected to the rib at a first end; a second electrode connected to the second slab at a second end of the second slab; and a high-k dielectric material disposed in or on a portion of each of the first slab and the second slab, thereby enabling capacitive coupling.

Abstract: An integrated circuit comprises: at least one photonic layer that includes one or more optical waveguides; a first optical coupler that couples at least a first optical mode outside of the photonic layer to a first waveguide in the photonic layer; a photonic device that includes one or more ports in the photonic layer; a first multi-port optical coupler that includes three or more ports in the photonic layer, including a first port optically coupled to the first optical coupler, a second port optically coupled to a first port of the photonic device, and a third port optically coupled to a first optical reflector configured to send substantially all optical power emitted from the third port of the first multi-port optical coupler back to the third port of the first multi-port optical coupler.

Abstract: A loss-based wavelength meter includes a first photodiode configured to measure power of monochromatic light; and a loss section having a monotonic wavelength dependency, wherein a wavelength of the monochromatic light is determined based on measurements of the first photodiode after the monochromatic light has gone through the loss section. This provides a compact implementation that may be used in integrated optics devices using silicon photonics as well as other embodiments.

Abstract: Driving an optical modulator is described. A control circuit generates first and second input voltages based on a target phase modulation between first and second optical waveguide arms of the optical modulator. An offset control circuit generates first and second offset signals. A linear modulator driver receives the first and second offset signals, generates a first output voltage for biasing the first optical waveguide arm using the first offset signal, and generates a second output voltage for biasing the second optical waveguide arm using the second offset signal. Feedback circuitry can feed the first and second output voltages to the offset control circuit, which can generate the first and second offset signals using the first and second output voltages. The output voltages bias the waveguide arms so the optical modulator operates close to the target phase modulation, even in the presence of manufacturing errors.

Abstract: An optical modulator device and method, including and utilizing: a first optical waveguide arm including one or more optical phase shifters, e.g., pn junctions, and configured to receive a first bias voltage Vbias1; and a second optical waveguide arm including one or more optical phase shifters, e.g., pn junctions, and configured to receive a second bias voltage Vbias2; wherein the first bias voltage Vbias1 and the second bias voltage Vbias2 are dissimilar, such that the first optical waveguide arm and the second optical waveguide arm exhibit a same phase modulation. Vbias1 and Vbias2 are selected such that the corresponding slopes V? of the associated phase shift versus applied bias voltage curves are equal. The optical modulator device further includes a driver coupled to the first optical waveguide arm and the second optical waveguide arm and including a current offset control circuit operable for providing Vbias1 and Vbias2.

Abstract: An optical modulator includes multiple segments including modulator segments and a Radio Frequency (RF) crossing segment where RF lines extending a length of the modulator cross one another. The present disclosure includes optimization of one or more of a geometry of the RF crossing and a location of the RF crossing segment along the length. The geometry is selected so that the RF crossing segment appears as another segment having similar characteristics as modulator segments. The location of the RF crossing segment is selected to balance out fabrication error and phase efficiency.

Abstract: A photodetector circuit is disclosed. The photodetector circuit includes an optical input configured to receive a source optical signal for detection by the photodetector circuit, an optical waveguide for coupling the optical input and at least one side of a plurality of sides of a photodiode, wherein the optical waveguide is configured to generate a first optical signal and a second optical signal from the source optical signal, and the photodiode coupled to the first optical waveguide, where the photodiode is illuminated on the at least one side by the first and second optical signals at different locations on the photodiode, where the photodiode generates a photocurrent based on the first and second optical signals reducing photocurrent saturation. Providing a delay between the first and second optical signals reduces an out-of-band frequency response of the photodiode circuit.

Abstract: An optical modulator includes a first arm and a second arm, each arm includes an arrangement with an equal amount of p-doped material and an equal amount of n-doped material, such that mask misalignment causes a same effect in both arms; and each arm includes a plurality of segments where electrodes connect for push-pull operation of the first arm and the second arm.